Celebrating 20 Years on the Web
TODAY IN SCIENCE HISTORY ®
Find science on or your birthday


Today in Science History - Quickie Quiz
Who said: “Science without religion is lame; religion without science is blind.”
more quiz questions >>
Thumbnail of John Locke (source)
John Locke
(19 Feb 1792 - 10 Jul 1856)

American geologist who invented tools for surveyors, including a surveyor’s compass, a collimating level and a gravity escapement for regulator clocks.


DR. JOHN LOCKE

EARLY OHIO SCIENTIST (1792-1856)

by ADOLPH E. WALLER

Associate Professor and Curator of the Botanic Garden
Ohio State University

[p.346] The nineteenth century in the United States suddenly swung into its expanding programs of research and education. No one was prepared for the impact of the increasing realization of the power over nature which man now possessed. The illusion of the perfectibility of all men through knowledge stretched undimmed. The inherent weaknesses of man and the snail’s pace of education were not yet perceived. Gigantic discovery was so close at hand that no one troubled to consider disappointments as more than temporary obstacles. A little proficiency in mathematics, languages, and the law marked the educated man. Scientific training was unknown. Science laboratories were just starting and the skills and techniques they were to impart were born on the spot.

The thesis that the medical colleges of the time were the sources of our trained scholars in the natural sciences has been stated in previous papers in this series. Three months at “Cambridge College” prepared Dr. Samuel P. Hildreth for his degree in medicine, after an apprenticeship with practicing physicians. Many others were likewise briefly exposed to formalized study. Dr. John Locke was more fortunate. His formal training lasted about three years.

Philadelphia and Cincinnati were early in asserting leadership in the quality of medical training offered. Many of the students trained in medicine were not as interested in its practice as in following the leads offered by their training in sciences. Our outstanding botanists and geologists of the 1830’s were thus educated. Dr. Locke’s story follows a similar pattern with the difference that he added physics to his earlier inclinations toward botany and geology. Perhaps it was from his keen observation of [p.347] the applications of botany to both medicine and agriculture. John Locke’s father also contributed to his son’s interest in the sciences.

Samuel Barron and Hannah Russel Locke, John’s parents, had lived at Lempster, New Hampshire, and Fryeburg, Maine, before going to settle near Bethel, Maine, on the Androscoggin River. John was then four years old. It was a choice location for the skilled artisan, Samuel Locke. There was a large tract of land to be purchased there. There was water power to operate his own saw- and grist-mills. There he built a shop which made him the outstanding millwright of the region. A number of people settled nearby and were given work in the mills and shop. The settlement came to be called Locke’s Mills.

Here young John grew up and received his early schooling which was supplemented by the varied assortment of books that his father’s library offered. As the community prospered a Methodist Meeting House and other establishments were added. For all of his skill as a machine builder in a young country hungry for machines the senior Locke found time to teach handicrafts, mathematics, and some languages to his son. He was also able to send him to Bridgeport, Connecticut, to attend an academy where he obtained the usual classical courses of study. John roamed the area collecting plants and hunting. It was a sad moment of realization for the father when young Locke decided he was not longer content to stay in Bethel to do what his father had successfully accomplished. John was eager to study medicine and began at Bethel in 1815 and shortly afterward with Dr. Twitchell at Keene. New Hampshire. A fragment of a diary shows the determination of a rebellious young citizen forced by his own decree away from his father’s abundance:

July 15, 1815. Left Bethel, arrived at Keen, Aug.15
Oct. 20, left Keen for New Haven tarried in Northfield.
Oct. 25, Northfield to West Springfield Expenses $0.85
Oct. 27, Thence to Weathersfield     do $0.72
Oct. 28, From Weathersfield to New Haven "   $0.90
$2.47

[p.348]

Title page of Outlines of Botany taken chiefly from Smith's Introduction; Containing An Explanation of Botanical Terms...
Facsimile of Title Page of Dr. Locke’s Botany.

[p.349] The journey was performed on horseback and it will be thought surprising that no more expense was involved. Economy was the object as I had, I thought, hardly money enough to bear my expenses at college. I ate milk, with sometimes a piece of apple pie with it only twice a day. Oct. 29 went to church in the chapel. Oct. 30 attended Professor Silliman’s lecture on chemistry.

A search made for a youthful portrait of John Locke has not been successful. A portrait of him as a man about 50 years of age shows a large, somewhat spare figure with a thin face and prominent cheek bones. He is said to have had clear blue eyes of an unusually sparkling quality. It is doubtful if the active student at Yale could have maintained his Spartan diet for long. He became Dr. Silliman’s assistant. With that great man’s recognition there was undoubtedly some means of subsistence provided. Besides, there may have been money from home.

Conversations with Silliman offered mental pabulum of a stronger sort. John was fired to emulate his chief in travels in Europe and other places. He began by a visit, in the summer of 1816, to Dr. Nathan Smith, the eminent founder of Dartmouth’s Medical School.

At Hanover he met also young Dr. Solon Smith who was struggling toward an education and toward increasing knowledge in a field of special interest to John. They had to become acquainted first in order to feel free to exchange ideas which were, perhaps, a little strange and not too welcome to some of their elders and preceptors. They both wanted to know how to identify plants. This was the common bond. Solon Smith owned a book they would both try to study. It was Dr. Jacob Bigelow’s Plants of the Vicinity of Boston, a new book, the first edition having been published in 1814. Presently it was to become the favorite New England version of the artificial system for naming plants, better known as the Linnean system. The system following natural orders and families was still regarded as revolutionary. It was some years before the North American flora would be so classified by Torrey or Gray. Jacob Bigelow’s book was therefore well known and twice was revised and enlarged. The third edition appeared in 1840, still demonstrating its usefulness to [p.350] amateur botanists. Dr. Bigelow’s scientific reputation rested on his lectures at Harvard and on his contributions to the United States Pharmacopoeia. His Plants of Boston was known as the most popular manual of its day.

What could not be accomplished by Solon Smith alone, namely, rouse an interest among Dartmouth students in plant studies, Locke and Smith together were able to do. Soon they had a number of the students tramping the hills around Hanover in search of specimens. To the delight of Dartmouth's medical college faculty, particularly to Nathan Smith, these became regularly organized field trips.

Back in New Haven the best parts of the next two years were busy ones for Locke who continued to assist Dr. Silliman in chemistry and at the same time continued his plant studies with the help of Dr. Eli Ives. He lectured in Portland, Boston, and Salem, and at Dartmouth and Yale. Probably with the enthusiastic backing of Dr. Nathan Smith he was offered a curatorship of the Cambridge Botanical Gardens by Dr. Jacob Bigelow. It seems, however, he was able to remain there only a short time, though not for lack of botanical qualifications. He was too outspoken on religious subjects for the peace of mind of some of the members of the Cambridge group. It is recorded, however, that he had been most pleasantly welcomed by Harvard’s president, John Thornton Kirkland, who found Locke sufficiently engaging to pay him the compliment of offering to study botany with him.

Though not yet equipped with his medical degree he was ready to combine medicine and botany on an expedition. The United States Frigate Macedonian was to sail under special orders to explore the Columbia River. It was to leave Boston Harbor on September 20, 1818. What an opportunity for Locke, probably still smarting a little from having lost his curatorship! He was warned that he would be badgered as a landlubber, a downeast country boy, and a noncombatant. Perhaps most of all the rugged seamen would resent the presence of a young intellectual. If tempers really broke he would have to stand in an “affair of honor” of large or small consequence. [p.351] When Locke appeared on board the Macedonian he was accompanied by a long mahogany box somewhat resembling a surgeon’s amputating case. This he contrived to drop on the deck in such an awkward manner that the lid flew open exposing a beautiful and complete outfit of dueling pistols. He was invited to join when pistol practice for the officers was announced. His skill in hitting any spot selected upon the targets convinced the crew that the surgeon’s mate was a man who knew how to handle small arms. He was no longer a stranger of uncertain position on shipboard.

Sailing orders for the Macedonian brought her off the Carolina coast in time to meet a West Indian hurricane of great violence. She was dismasted and so beaten by the waves as to be almost destroyed. After the storm she limped slowly back to Norfolk. Upon deliberation, the Navy abandoned the Columbia River operation. Locke applied for his discharge and made his way back to New Haven as quickly as he could. life on the sea was a gamble. Others might take it if they chose. For him there was other work.

He set in at once to complete his requirements for a medical degree at Yale and in 1819 was graduated with the sixth class. Dr. Eli Iyes taught Materia Medica and Botany, the usual arrangement made in the medical curricula of that period. He had a reputation for scholarship and had published a brief list of the plants of New Haven as early as 1811. This was later extended with the help of his students to more than a thousand plants. Also at his own expense he had set out a botanical garden near the college.1 Locke must have spent a great deal of his time in studying the collections and he resolved to prepare a manual for students which would quickly familiarize the beginner with the meanings of terms used in classification.

Grid of 12 drawings of various examples of flowers, illustrating their different numbers of stamens.
Plate 15A

[p.352] Facsimile of Illustration in Locke's Botany (Plate 15A.)

[p.353] Explanatory page for illustration.

EXPLANATION OF PLATES.
PLATE 15. A.
CLASSES—See Frontispiece.

This plate contains a figure of a flower in each of the 24 Classes. With the exception of 1, 9, and 23, they are either native or commonly cultivated.

Fig. 1. Monandria, 1 stamen; Mare’s-tail, Hippuris culgaris. Native of Britain.
    This is an example also of the order Monogynia, having 1 pistil.
2. Diandria, 2 stamens; Speedwell, Veronica.
3. Triandria, 3 stamens; Common Timothy-grass or Herds-grass, Phleum Pratense,
    much magnified.
a. The entire Floret, having three stamens and two feathered styles projecting from the two compressed glumes which enclose them at the base.
b. The Pistil shown separate, consisting of the germen and two feathered styles.
    This is an example also of the order Digynia, having 2 styles.
4. Tetrandria, 4 stamens; Cornel, Cornus paniculata, somewhat magnified.
5. Pentandria, 5 stamens; Common Elder, Sambucus niger, magnified.
    It is an example also of the order Tryginia, having three sessile stigmas.
6. Hexandria, 6 stamens; Barberry, Berberis vulgaris.
7. Heptandria, 7 stamens; Chickweed wintergreen, Trientalis Europeus.
8. Octandria, 8 stamens; Dwarf tree primrose, Oenothera punnila.
9. Enneandria, 9 stamens; Flowering Rush, Butomus umbellatus. Native of Britain.
    This is also an example of the order Hexagynia, having 6 pistils.
10. Decandria, 10 stamens; Broad-leaved Laurel or Lamb-kill, Kalmia latifolia.
11. Dodecandria, 12 to 19 stamens; Houseleek, Sempervivum tectorum.

To prepare the illustrations for this, Locke learned the art of engraving. His father's careful instructions in the use of tools served him well, and his own skills and desires as a craftsman [p.354] enabled him to complete his task. It was a teaching aid not paralleled in the United States. The Linnean system of classification was illustrated with examples of North American species. These would be readily obtainable for class use. The descriptive writing of Jacob Bigelow’s book was supplemented by figures of the plants which beginners could not fail to grasp.

The dedication of Locke’s Outlines of Botany was to “Jacob Bigelow, Rumford Professor of Materia Medica, Harvard.” In his preface he separates elementary from practical work and characterizes his work as showing the same difference that a dictionary or grammar would bear toward works of history or poetry. His raison d’etre gives the following recommendation to plant study: (1) medicine, the arts, and agriculture depend upon it; (2) it is a rich source of pleasure; (3) it affords discipline by means of which methodizing a subject and analyzing it may be learned; (4) it offers spiritual inspiration. “The study of nature is the elder scripture written by the hand of the Creator.” Instructors of botany today will take heart in the following item from his preface: “From what little experience I have had in instructing I cannot recommend to teachers to oblige their pupils to commit any of the following pages formally to memory, in doing which they are by no means certain to get the ideas.”

Published in Boston in 1819, this work must have come to Dr. Bigelow’s notice and won the approval of President Kirkland. When Dr. Bigelow brought out his second edition of the Plants of Boston (1824), he might well have used Locke’s illustrations. An excellent teaching, manual redounding to the credit of both Locke and himself would have been the result. By this time Locke was in Ohio where other interests were crowding into his busy life. Bigelow’s second edition was too late for him. An associate of Locke said of him that:

Scarcely four years had elapsed since he left the valley of the Androscoggin a plain country boy, and yet, within that time he had secured the favor of distinguished men, had received the appointment of Assistant Surgeon in the Navy, had become a Doctor of Medicine, an author of a popular scientific work, a teacher and lecturer in colleges, not [p.355] only to pupils but to professors. All this was accomplished without one dollar of patronage or support except that created by his own exertions.2

He was not to find a remunerative medical practice however. Things might have been different had he remained aboard ship or had he read medicine under a physician. Medical colleges offered no instruction in dealing with patients, and the hard life and meagre living of a country doctor offered little to attract him. He accepted the position of assistant to Colonel Dunham who was the proprietor and head of an academy for girls at Windsor, Vermont. Here his gifts as a teacher could again shine forth. When Colonel Dunham developed the plan for establishing a similar school in Lexington, Kentucky, Locke agreed to go there for that purpose. He felt that New England was dominated by religious intolerance and he preferred to live in another part of the country.

A boyhood memory was a probable factor in this decision. His father had built a Methodist Meeting House at Locke's Mills giving both land and materials for construction. By an old Massachusetts law, which applied in Maine as part of Massachusetts, a tax for the support of the prevailing sect was levied on members of other sects unless exempted by payments to the support of their own denomination. Locke, Senior, refused to qualify under the exemption clause and also refused to pay the assessed cash tax because of his donations. He regarded the law as invasion of religious liberty. John witnessed the officers of the law driving away cattle from his father’s farm, having seized them in lieu of tax money. This injustice so strongly impressed itself upon John that he determined he would some day live in a place where there was less upholding of the letter of religious administration and greater tolerance for human rights.

Since Colonel Dunham’s plans had altered, Locke came to Kentucky alone and founded the Lexington Academy in 1821. Little is known about the Kentucky school. He may have made some important acquaintances in Lexington. It probably served [p.356] as a means of establishing Locke as an educator in that section of the country. It likewise was the means of bringing him one step nearer establishing his residence in Cincinnati which was to become his permanent residence.

One authority wrote:

He began his work in Lexington, Ky., in 1821 and soon evinced his superior talents as a teacher. In 1822 Locke had occasion to visit Cincinnati, making the trip from Lexington on horseback. “As he emerged from the woods of Kentucky, and rose over the hill south of Newport, the valley surrounding the now Queen City opened to his admiring view. On approaching the city the rattling of drays, the clink of hammers, the smoke of factories, the rush of steamboats, the firing of signals of arrivals and departures, acted upon his mind with all the force of enchantment. He fell in love with the Queen City and decided to make his home here.” Ethan Stone, that remarkable pioneer and philanthropist, took an interest in the young stranger and aided him in establishing a non-sectarian school for young ladies (Dr. Locke’s School) which enjoyed a great reputation for many years and was patronized by the best people. The school was located on the east side of Walnut Street, between Third and Fourth Streets.3

Other friends soon included the ministers of several denominations of churches in Cincinnati. Dr. Joshua L. Wilson and Dr. Ruter, whose daughter became a pupil of Locke’s school. There was no concealment or evasion in respect to moral or religious instruction in Locke’s academy. None was offered, teaching being construed as secular. Yet he was firm in making opportunities to “impress on the minds of these pupils the great principles of religion, the existence and attributes of Diety, the expedience and necessity of cultivating social virtues. Open your school then that it may be patronized by all denominations,” said Dr. Ruter, “and great good will result.”

In a History of Cincinnati and Hamilton County is the following statement concerning Locke’s school:

In 1823, Dr. John Locke, a man of science and of some progressive views in education, organized in Cincinnati a private school for girls, under the name of Locke’s Female Academy. In this school, as in others established about the same time in the Ohio Valley, some of the methods of Pestalozzi were followed. It is interesting and suggestive to reflect [p.357] that just at the time when the old Swiss reformer was nearing the close of his life, dejected from the apparent failure of his toils, enthusiastic teachers on the banks of the Ohio river were putting his wise advice into practice.4

A family weekly magazine published at the time praised the school thus: “It was truly gratifying to witness the rapid improvements of the pupils generally, in all the branches of science taught in this institution, and more particularly in those of Natural and Moral Philosophy and Botany.”5 During the twelve years of Locke’s proprietorship somewhere near four hundred pupils received an education in the school. Mentioned for high attainment in the early days of the school were Amanda Drake, Mary Longworth, Sarah and Jane Loring, Frances Wilson, Jane Keyes, Eliza Longworth, Selima Morris, Charlotte and Mary Rogers, Elizabeth Hamilton, and Julia Burnet.

Mrs. Trollope who usually displayed unlimited irritation in her criticism of Cincinnati and its inhabitants gave some space to the school following her attendance at one of the commencements. She described Dr. Locke as a

gentleman who appears to have liberal and enlarged opinions on the subject of female education … [and] perceived, with some surprise, that the higher branches of science were among the studies of the pretty creatures I saw assembled there. … ‘A quarter’s’ mathematics, or ‘two quarters’ political economy, moral philosophy, algebra and quadratic equations, would seldom, I should think, enable the teacher and the scholar, by their joint efforts, to lay in such a stock of these sciences as would stand the wear and tear of half a score of children and one help.6

However, Mrs. Trollope’s judgment has been seriously questioned. Even her own son, Anthony, wrote of her that “no observer was certainly ever less qualified to judge of the prospects or even of the happiness of a young people.”7

Contemporary writers in Cincinnati agreed that Mrs. Trollope and her English friend, Miss Frances Wright, stirred a great deal of discussion because of their unconventional attitudes.8 In [p.358] spite of bitter opposition they probably caused people to think about some of the current problems of education and they may have led the way to reform. Locke’s school is noteworthy because it was turned definitely toward the concepts of modern education. During its fourteen years, it would have established Dr. Locke’s reputation if he had never engaged in any other occupation. He became famous for simple lucid exposition. His method of asking questions designed to inculcate thinking habits made the school known throughout the nation.

His methods were based on the principles of Pestalozzi. During his brief association with educational methods while at Windsor, Vermont, and his attempt to work alone while at Lexington, he must have had an opportunity to try several methods. There is also the possibility that he met Dr. Joseph Buchanan while in Lexington, acquiring from this original, though somewhat frustrated genius, the firm conviction that mathematics and science should become a part of a liberal education. If Locke's school was not the first in the United States to try the Pestalozzian method, it was certainty the first of such schools in the Ohio Valley. When Dr. Daniel Drake later turned to educational problems he failed to acknowledge Locke’s plan probably because Locke had left his school and was a professor in the Ohio College of Medicine, a rival of Drake’s Cincinnati College.

Dr. Locke also began lectures in the Mechanics’ Institute. He is credited with being one of the early workers or founders of. that valuable source of instruction. He began the lectures in his own home and, when that became too crowded, gave them in a building on Walnut Street occupied by a Baptist congregation. Later, after Mrs. Trollope’s financial debacle the Institute occupied her bazaar.

In 1825, John Locke was married into one of Cincinnati’s distinguished families. Mary Morris, of Newark, New Jersey, and niece of Nicholas Longworth, became his bride. In the course of time six sons and four daughters were born.9 More and more [p.359] John Locke was devoting time to his own investigations in electricity and less to the preparatory school. He was ready in 1835 to accept an appointment as Professor of Chemistry in the Medical College of Ohio. He also was becoming interested in geological studies.

Probably his first interest in geological questions had come from being asked to make chemical analyses of various minerals submitted to him. The other possibility is that he had privately begun some surveys of his own, the direct result of his student days when he had served as assistant to Professor Silliman. His lectures at the Mechanics’ Institute would have promoted an attempt to keep abreast of new publications. He may also have met Dr. Samuel P. Hildreth at some of the medical meetings beginning to be held at that time. Dr. Hildreth had been writing on the geology of Ohio and publishing, among other places, in Silliman's Journal as the American Journal of Science and Arts was popularly known. Dr. Hildreth had also served as chairman of the governor's committee to report on the best method of obtaining a complete geological survey of Ohio.10

Dr. Locke contributed to the Second Annual Report of the Geological Survey, along with Charles Whittlesey, J. W. Foster, Caleb Briggs, and Dr. J. P. Kirtland, with W. W. Mather as Chief Geologist. Dr. Locke’s report was the last one received as he was lecturing and traveling in England during 1837. His opening sentence shows his eminently practical point of view and his desire as an educator to reach his public. “As the geological reports are intended, in part at least, for the distribution of useful information among the people, it will be necessary to introduce occasionally, though briefly as possible, such elementary explanations as will enable them to understand the subject discussed.”11 He was assigned the southwestern quarter of the State. He began with the chemical analysis of the limestones which had been included in the first report of the committee as well. The limestones were not fully classified as they are at present, of course, [p.360] and he simply states them by color as “blue limestone” or as “cliff limestone.” The latter derived its name originally from early reports of surveys made in Scotland. It was the general name for limestones forming cliffs. Locke wrote:

In accordance with this nomenclature a creek which falls into the Ohio below Madison (Ia.) [Indiana] and makes in its course some magnificent leaps cover the cliff limestone has received the name of “Clifty Creek” and the cascade that of “Clifty falls,” the t being added agreeably to a common provincialism of the west which makes a skiff, a “skift,” a cliff, a “clift,” etc. Clifton, a town north of Xenia, is just at the commencement of the same stone, and has borrowed its name from it.12

He surveyed and drew with great skill a diagrammatic section of the valley and channel of the Ohio River at Cincinnati from Keys Hill in Ohio to Botany Hill in Kentucky and records the high water of the Ohio in 1832, sixty-two feet above its low water level of 1838.13

Of the importance of studying the dip of geological formations he has this to say:

The strata are nearly horizontal, and having a slight and irregular undulation, the dip is with difficulty ascertained, while one confines his attention to the layers of the same formation, for example, to the blue limestone about Cincinnati. The inclinations resulting from undulation, are seldom more than one foot in 45; unless water be contiguous to mark the level, the strata appear to the eye to be quite horizontal. I have examined the inclination of the strata of blue limestone about Cincinnati very particularly with the leveling instrument, and have sometimes found a uniform and consistent dip for half a mile; in another locality the dip would be in an opposite direction. The strata in the bed of the Ohio at its lowest stage in Sept. 1838, showed, by comparison with the surface of the water, that these local undulations were extremely irregular, presenting inclinations which vary in all possible directions, in planes continued uniform not generally more than one fourth of a mile. A single stratum cannot in general be identified far enough to determine on the whole, whether it has, independent of local undulations, an absolute dip. However, when we examine the several formations, previously named, on a large scale, the dip becomes very evident; and as one formation sinks gradually below the surface, and another superior one presents itself, gives rise to those important changes in the face and productions of the country, which we should hardly attribute to a slope so moderate as one inch in a rod. By a [p.361] correspondence held between Dr. Owen, the Geologist of Indiana and myself it has been ascertained that the strata slope downward each way from a line not far from that between Ohio and Indiana pitching eastwardly in Ohio and westwardly in Indiana in such a manner that the cliff limestone, which shows itself not many miles east and west of Richmond, in Indiana, descends and comes to the bed of the Ohio river, at the east side of Adams Co., in Ohio, and at the falls of the Ohio, at Louisville. It follows as a consequence of this arrangement that the out-cropping edges of the strata present themselves at the surface in the same order in the two States, but proceeding in opposite directions. For example, on ascending the Ohio eastwardly, we meet with blue limestone, cliff limestone, slate, fine sandstone, conglomerate, and coal. On descending the Ohio westwardly, we meet with the same things, in the same order, viz; blue limestone, cliff limestone, slate, &c.14

This quotation is given in full as a splendid example of his simple explanations and descriptions. Here Locke is the student in the field beckoning the stay-at-home to venture out of doors and try first hand an interpretation of nature. This is also the first description of the great limestone arch, “the Cincinnati anticline,” as it came to be called in the textbooks. Locke had given up his private school but he was still the educator addressing a larger unseen audience as well as the special group for whom his remarks were prepared.

He was also eager to present the value of the study of geology to the average citizen. On the map he prepared of Adams County he placed a section connecting with Scioto County on the east. He showed by this means that the coals of Scioto County, because of their dip toward the east and their rise westward, would be in the air 1,160 feet above the level of western Adams County. At a glance anyone would know that searching for coal in Adams County would be useless. It is believed this is the first time a geological report carried so much useful information in such a simple, graphic way. Part of its purpose was to demonstrate the practical side of the survey to the State legislative assembly. However, it was not until thirty years later under John S. Newberry that the work was resumed.

For some years, Dr. Locke had been investigating terrestrial [362] magnetism and the deviation from true north noted in the hand of the compass. While he had been in England in 1837, Locke had met some of the British investigators of this problem. He was able to add data for comparison with the European published results. He continued these investigations for a number of years and soon was a recognized leader in this field. Possessed of an inquiring mind and a passion for designing or improving pieces of equipment he produced a “microscopic” compass and the famous Locke level still used by civil engineers. Both of these were employed first by him in his own survey work and then offered for use to others.

Locke’s connection with the Geological Survey produced a number of results of permanent value to the State. It was through his researches on the variation of the magnetic needle that the corrections in the separate tracts of land in the survey of the State of Ohio could be made. The Virginia Military Lands were parceled out to the owners of claims without any regularity or system. Locke helped to establish order in this confusion by his knowledge of the behavior of the magnetic compass. He was also able to locate iron deposits with a special instrument he developed, and made a journey into southeastern Ohio with other members of the Survey for that purpose. It was clear to the members of the Geological Survey that much of the school land originally appropriated to the State had been sold too quickly. Without a geological appraisal the land had been sold on the basis of its potential agricultural value only. The intelligent work of men like Hildreth and Locke unfortunately could not prevail in the moulding of public opinion. Instead of squandering most of its land grant Ohio might have profited as was later possible in some of the other states, notably Minnesota.

Locke was to have prepared detailed surveys of both Butler and Adams counties. He completed Adams before the work was abandoned. The survey of Adams County was thus appraised years later by Evans and Stivers:

There has never been but one geological survey of Adams County, and that was made by Prof. John Locke, Assistant State Geologist, in [p.363] 1838. There is a more recent report but it does not at all cover the county. Prof. Locke's report is so comprehensive and withal so plain that anyone by reading it may acquire much valuable knowledge of the geological formations of Adams County. It is however necessary to note some changes in classification and nomenclature in accordance with present usage.15

On April 25, 1838, the disaster to the river steamer Moselle occurred. It was the worst accident of its kind. The boilers had exploded and the ship was burned. Since a number of lives were lost, the citizens of Cincinnati called upon Dr. Locke to head a committee of investigation. With his usual thoroughness Locke examined the possible causes of the explosion. He centered blame upon the ship builders and owners, accusing them of neglect in taking precautions to guard the lives of crews and passengers. His report was widely read. The discussion of his report became an important factor in establishing modern laws to protect all who use steamboat navigation.

Dr. Locke may have accepted the chair of chemistry in the Medical College of Ohio in 1835, though his actual teaching seems to have begun in 1837. Locke went abroad between 1835 and 1837, for the purpose of purchasing new apparatus for the courses he intended to teach. His connection with the college is clearer after 1837, when the faculty was reorganized and the rivalry with the Cincinnati College was declining.

He entered this period of teaching fully aware of the storms that had centered around the medical faculties or one might also say around the personality of Daniel Drake. By the time Locke joined the faculty of the Medical College of Ohio, originally founded by Drake, Drake had also founded two other medical faculties in Cincinnati, the Medical Department of Miami University which lasted only a year and from which Drake resigned when it was included in the Ohio College, and the Medical Department of the Cincinnati College which lasted from 1831 until 1839. Meanwhile Drake had taught at Transylyania University and at Jefferson College in Philadelphia. Drake's brilliant, turbulent [p.364] career, full of zeal and ambitions to be the foremost medical teacher in Cincinnati, touched the lives of all the prominent medical, scientific, and public spirited citizens of the town. Locke should have been forewarned by the frequent upsets in the medical faculties. This did not prove to be the fact.

When the political intrigues which had been fomented in the Ohio College resulted in Locke’s dismissal in 1849-50, he was stunned. Although he was reinstated and served two more years he no longer retained the enthusiasm for the college that carried him through the creative years he had spent there. It was during this period of about fourteen years that Locke proved to be one of the most remarkable figures in the advancement of science in his time. It is the aim of the following paragraphs to show this phase of Locke’s life.

Locke had carried with him to England his observations of the deviations of the magnetic compass and thus was able to make comparisons with the results obtained in England. Col. Sabine, of Woolwich, wrote to Locke, November 20, 1843: “Permit me to express hope for early publication of your observations comparing Cincinnati, Toronto … on terrestrial magnetism. If there should prove a difficulty causing a serious delay in the publication of your discoveries in the United States, I cannot doubt that either the Royal Society or the British association would be very proud to receive them and print them.”16 There was sound practicality in this request. The accuracy of surveying and navigation were still too dependent upon the erratic compass.

He invented a thermoscopic galvanometer of great sensitivity and demonstrated it to members of the British Association. Probably at this time he met Professor Wheatstone and Sir David Brewster who were interested in his experiments on optics which they were likewise investigating. G. M. Roe adds another factual nugget:

In connection with this trip of Dr. Locke to Europe may be mentioned a circumstance illustrative of the uncertainties regarding municipal action. The city of Cincinnati then used an incorrect linear measure and requested Dr. Locke to secure a standard. He did so, having two made [p.365] and compared with the English standard by William Simms, who made the originals for the British Government. One of these is 413 millionth of an inch too long, the other 150 millionth of an inch too short. (Standards can not be made exact but practically are so by having a known error.) The city authorities failed to reimburse Dr. Locke, and the measures … still remain in the hands of his heirs. The measures are now of great interest as the original English standards are under seal, and can only be opened by an act of Parliament.17

The acquaintances he made abroad probably caused him to think about the advantages of systematic gatherings of scientists. He began to attend meetings of the newly organized Association of American Geologists. He did not attend the founding meeting held at the Franklin Institute in April 1840. He may have been at that time with David Dale Owen on the Indiana Geological Survey, the report of which was published that year. However, W. W. Mather was present. Mather had known Locke for his work on the Ohio survey and may have seen to it that Locke came to the second meeting of the Association, and thus tied him in with the group that included Edward Hitchcock, L. C. Beck, Douglass Houghton, J. N. Nicollet, A. D. Bache, and others.

When the second meeting was held beginning April 5, 1841, at the Academy of Natural Sciences in Philadelphia, Locke was appointed one of the committee to plan the conduct of business. From the previous year a committee to discuss mineral manures had been held over. Locke took part in that discussion. W. W. Mather asked to postpone his paper on the “Drift” and Locke read a paper on the “Geology of Some Parts of the U. S. West of the Allegany Mountains.” In this he offered some comparisons between the position and age of European formations and those he had studied in Ohio and Indiana. This brought forth some discussion and objections that were quite natural since “cliff limestone” and “blue limestone,” the currently employed terms, were inadequate for comparative studies.

In a later session he described a new species of trilobite found at Cincinnati and named by him Isotelus maximus. He demonstrated by casts one specimen 9¾ inches long and fragments [p366] of another 19½ inches long. The latter was the largest trilobite known. In another paper he discussed the “diluvial scratches” that he had observed in limestone. He called attention to variations in the widths of the lines or grooves, up to ½ inch broad. Some were “1/8 inch deep, scaled rough in the bottom as if they had been ploughed by an iron chisel properly set and carried forward with an irresistible force.” From their exact straightness and parallelism Locke drew the inference, now accepted as factual, that the lines had been formed “by a body of immense weight, moving with a momentum scarcely affected by the resistance offered by the cutting of the grooves.” He pointed out that one set of grooves might be crossed at an angle by another, but that the parallelism of each set remained.18

All of this data on striae must have set the geologists thinking that perhaps diluvial was not the way to describe these scratches. Not many of the members present had been West. There was Nicollet who had explored in Missouri. He, Douglass Houghton, Bela Hubbard, Mather, D. D. Owen, Locke, H. D. Rogers, also of the Medical College of Ohio, and possibly some others were opening up the explorations of the continent. The great continental ice theory was not to be announced by Agassiz for some years. The announcement of the parallel nature of the grooves must have made that second session of the geologists pretty much Locke’s session.

At the second meeting, also held in Philadelphia, the president, Rev. Professor Edward Hitchcock, referred to Locke's observations. There is not available a first hand report of all that Locke had included in his paper. Hitchcock’s address depends in part on remarks that must have been made by Locke. Hitchcock brings out the point that the grooves even cross sharp ridges without alteration of direction. It was difficult after that session to attribute all the facts about drift to a deluge. The stage was being set during these meetings for the modern discussions of glacial geology that were to follow in the next few years.

The place of leadership that Locke was filling in the early [p.367] years of the Association of American Geologists continued during the following meetings. At Boston in 1842, Dr. Samuel Morton did not arrive on time and Locke was asked to take the chair. A constitution was adopted, the name being altered to Association of American Geologists and Naturalists. Its cosmopolitan aspect was attested by the presence of Charles Lyell. As in the previous year, Locke presented papers on a diversity of topics. His paper on “Ancient Earthworks in Ohio” led to the formation of a committee to examine and report on the western mounds. Locke, J. N. Nicollet, John H. Blake, Dr. George Engelman, of course Hildreth, Prof. Troost, and Dr. B. B. Brown were named. A search for any work by this committee fails to turn up a report, however.

Locke also presented a paper on a new instrument he had invented, a reflecting level and goniometer. He also described a reflecting compass. His skill in designing instruments suited to his problems was second only to his ingenuity in measuring and observing facts others neglected. He was a teacher because he was ready to deal with the situation at hand. He returned to plant studies with a paper on a prostrate forest under the Ohio diluvium. Not presented at the meeting was a published report on observations made at Baltimore on the dipping compass. To test his observations his friends, Major Graham, Nicollet, and Bache, made similar use of his instruments. He also published a drawing of the large trilobite, changing the name to Isotelus megistor.19

Locke published a report on mineral lands ordered to be surveyed by Congress in 1839. This had carried him to the lead regions in Wisconsin and in Missouri. His observations on the subject of terrestrial magnetism carried him to the north side of Lake Superior.20 He also became interested in transportation problems at Sault Sainte Marie and was asked by the War Department to prepare a report on the subject of a ship canal around the rapids. He observed the granite boulders along the lake shores [p.368] with strong doubts as to their usefulness in canal construction. He stated that the want of materials for such a work need not be any impediment as the limestone of Drummond’s Island could be easily transported to the Sault. He made an observation contrary to a recommendation which had been made to the War Department with regard to the depth of the canal. He doubted whether vessels drawing more than six feet of water could at all times navigate St. Mary's River on account of two bars, one of rock at the Nebish Rapids and the other of mud in Lake Huron. Therefore it would hardly be necessary to make the proposed canal twelve feet deep as had been suggested. Since Locke's time more than a century of thoughtful experimentation has attempted to adjust the ore and grain cargoes, the ships themselves, and the docking facilities to the fundamental geological problems his alert eyes reported in his “hasty” observations.

Then the Doctor, the almost forgotten person in the several John Lockes of whom the reader must by this time be aware, came forward to express himself.

There remains another consideration which although not immediately connected with wealth is still important in furnishing that without which wealth cannot be enjoyed. We venture to urge the opening of Lake Superior to steam navigation in order to facilitate the access of thousands of invalids to a region so picturesque, so novel, and so invigorating as can scarcely be equalled on the globe.

He mentioned the weariness of life created by the “Miasmata of the Mississippi and the calm dry heat of a summer in the Southwest.” He grew poetic in recommending an early escape to the “pure water, the clear atmosphere, the temperate summer climate, the rugged fir clad rocks, the piney glades carpeted with reindeer licken and hung with the dangling usnea.” It was probably nostalgia for his own boyhood in Maine after a succession of sultry summers in the Middle West that brought the enraptured praise that follows:

The canal being opened the citizens of New York escaping from dust and ennui and the resident of New Orleans fleeing from the pestilence of the summer months may be speedily wafted to a meeting at Porter’s Island, at Isle Royale or at La Point and there enjoy most of the Boreau wonders [p.369] of which they have read in the voyages and travels of Ross, Franklin and others and there in the day admire the delusive mirage of the distant shores and in the night the portentous streamers of the aurora.

The fifth annual meeting of the Association of American Geologists and Naturalists was held in 1844 at Washington. Dr. Locke served as chairman, and Dr. Douglass Houghton as treasurer. Dr. David D. Owen who had been elected secretary was not present. Locke read a paper on the connection between geology and magnetism, since he had always made both kinds of observations on his field trips. He noted that the greatest magnetic force was to be found in the Lake Superior region. Douglass Houghton read a paper on the importance of connecting geological surveys with linear surveys of public lands. The Washington meeting, close to the seat of Congress, contained in the papers of these two investigators a symposium which, if noticed, would serve to call the attention of government officers to the needs of research and exploration of our natural resources. John Locke, the quiet teacher, was on the way to becoming a national figure.

In the paper he read at the meeting he remarked:

In the year 1838, I began to examine the elements of terrestrial magnetism, including dip declination and intensity, both horizontal and total, over various parts of the United States. Every year since I have made journeys to extend this kind of research until now I have embraced in a general way the region from Cambridge, Mass. westward to the extreme of Iowa and. from the middle of Kentucky northward to the north side of Lake Superior. It was but natural that I should note the geology of the substratum at each station; and on reducing my observations and putting them into tabular form I examined the properties of each group extending over rocks of a similar kind and found so far as I had examined some general indications of which classes of rocks might be distinguished although concealed at considerable depths, the magnetical instruments in this respect answering the general purpose of a mineral or divining rod.22

This may have contained a little over-extension of his enthusiasm—yet in the Lake Superior region compasses were always showing crazy local deflections. What excitement was concealed [p.370] beneath the lofty cool words of Locke’s paper! He was talking to the men who knew better perhaps than any other group in America the lack of knowledge of our mineral resources. They were the custodians at that moment of enormous potential wealth before which even Aladdin’s lamp would have blinked out.

Present at the meeting were Douglass Houghton whose name will always be associated with Michigan and Minnesota, Wm. B. Rogers, H. D. Rogers, and A. D. Bache of the Coast Survey Office. Capt. Wilkes of the United States Exploring Expedition invited the company to visit the collections housed at the U. S. Patent Office. An invitation was extended likewise from the U. S. Naval Observatory. To a number of the men he met, Locke was shortly to become indebted for attention they gave to other of his inventions.

He had strung a telegraph line — the first one in Cincinnati — from the laboratory where he worked in the Ohio Medical College to his home. He had trained two of his sons to help him put together various instruments and pieces of scientific apparatus he continually was designing. Excerpts from Locke’s report seem the most appropriate for describing his greatest invention. This instrument was the electro-chronograph. “My attention was first drawn practically to the subject of the combination of clocks and electrical machinery for producing useful results in 1844 and ’45.”23 He had obtained a lathe and a set of tools from the sculptor, Hiram Powers. Whenever he needed a new piece of apparatus to demonstrate a principle he was able to design an effective device. In consequence the lectures he offered attracted a distinguished audience. His assistants were Thomas K. Beecher and his sons John Locke, Jr., and Joseph M. Locke.

He devised two types of electrotomes, one with a conducting pendulum swinging through a mercury cup, the other a wheel with pins or teeth to break the circuit of tripping a tilt hammer. This second form avoided friction. It then occurred to him, particularly after correspondence with Sears C. Walker of the Coast Survey Office, that an improvement could be made on the [p.371] observations of time signals and star signals made in the calculation of longitude. Heretofore these had been made by ordinary clock readings and manual contact with an electric circuit breaker to send signals by telegraph to another station. Due to an uncertain loss of time the observations were not at the level of accuracy desired.

Locke then thought of using the Morse register on which a magnet marked traces on a paper ribbon. By this means any station connected with the observer could have an event recorded at the split second the circuit-breaker key was moved. “Almost every astronomical observer has intuitively felt a desire to have some kind of a chronograph with which to subdivide a second and record fractionally the punctum of observation.” Sears C. Walker wrote:

Dr. John Locke of Cincinnati, has invented a very cheap and simple instrument which can be attached to the same pivot along with the second hand of any clock, and which will, when put in connection with the telegraphic circuit, make the clock beat at the same instant all along the line. The hours, minutes and seconds, may be registered on the fillet of paper, and by striking on the telegraphic key at the instant of any occurrence, the date of it is recorded on the same paper to the hundredth of a second. This invention will be useful for many practical purposes. It makes the current of time visible to the eye in a permanent record. It does not change the rate of going of the most delicate clock. It will doubtless be applied hereafter to many purposes for the advancement of science; such as the determination of geographical longitude, in connection with transit instruments, measurement of the velocity of sound; perhaps, if the circuit be long enough, of lightning itself.24

Lieutenant M. F. Maury, Superintendent of the National Observatory, wrote in a letter to Hon. John Y. Mason, Secretary of the Navy, this graphic account of the use of the electro-chronograph:

Thus the astronomer in Boston observes the transit of a star as it flits through the field of his instrument, and crosses the meridian of that place. Instead of looking at a clock before him, and noting the time in the usual way, he touches a key, and the clock here subdivides his seconds to the minutest fraction, and records the time with unerring accuracy. [p.372] The astronomer in Washington waits for the same star to cross his meridian, and, as it does [the key for circuit breaking on] Dr. Locke’s magnetic clock is again touched; it divides the seconds and records the time for him with equal precision. The difference between these two times is the longitude of Boston from the meridian of Washington. …

And thus this problem, which has vexed astronomers and navigators, and perplexed the world for ages, is reduced at once, by American ingenuity, to a form and method the most simple and accurate. While the process is so much simplified, the results are greatly refined. In one night the longitude may be determined with far more accuracy by means of a magnetic telegraph and clock, than it can by years of observation according to any other method that has ever been tried.25

The Coast Survey had made an arrangement with the Telegraph Company in Cincinnati to have a line extend through Dr. Locke’s house. On November 17, 1848, this experiment of observing longitude with Locke’s instruments was tried for the first time and it was successful. The model instruments had been completed by the fourth of November. Dr. A. D. Bache communicated a full report to Congress in December of that year and to Dr. Locke a special Congressional award of ten thousand dollars was the official recognition that the representation made on the part of his colleagues in this advance into the realm of science was approved.

This invention would be a happy, elevated note on which to conclude the account of the work of Dr. John Locke. One must not forget that his work in the fields of physics and astronomy sprung from the lectures on chemistry he conducted in the Ohio Medical College. That was always an institution given to personality conflicts among the faculty members. Locke had begun his work there during one of the frequent reorganizations of the faculty personnel. He was to leave it in the same manner. The blow of being asked to resign was too much for him to bear, even though he knew it was a political quarrel that forced his dismissal. He was shortly afterward reinstated, but the damage to his spirit of loyalty had been too great to rekindle his old enthusiasm for the school. He remained two years after reinstatement [p.373] but moved to Lebanon, Ohio, and there managed a preparatory school. This was too weak a challenge to his broad grasp of the world of science. But he had no further taste for original investigation if he and his labors were to be subject to political vagaries.

At the meeting held in 1851 in Cincinnati of the American Association for the Advancement of Science, a lineal descendant of the old Association of Geologists and Naturalists. over which he had presided, Locke was not present. His son, L. T. Locke of Nashua, New Hampshire, is listed among members of the association, but his name is dramatically lacking. His friend and associate who had done much to praise the electro-chronograph, A. D. Bache, served as president. O.D. Mitchell, the Director of Astronomical Observatory of Cincinnati, delivered an address on the longitude of Cincinnati, and Sears Walker gave a report, but the only mention of the name of Locke is an acknowledgement of a chronometer loaned by him.26 To Locke it was easier to subdivide seconds than it was to regain emotional composure and balance.

He made one strong effort to return to his first interest in the field of science—the plant world. He delivered at Lebanon an address, “On the means of renovating worn out farms.” After discussing declining fertility in soils and the methods of combatting this, he recommends the establishment of libraries of agricultural schools and an agricultural survey. It is interesting to note that a paper by N. S. Townshend is contained in this same volume.27 The brilliant genius of John Locke was dimmed. He was not looking backward but was passing something of his spirit to others who would look to the natural resources of Ohio and their future development.

1 Andrew D. Rodgers, “Noble Fellow” — William Starling Sullivant (New York, 1940), 81.
2 M. B. Wright, An Address on the Life and Character of the Late Professor John Locke (Cincinnati, n. d.), 14.
3 Otto Juettner, Daniel Drake and His Followers (Cincinnati, 1909), 156.
4 History of Cincinnati and Hamilton County, Ohio, Their Past and Present (Cincinnati, 1894), 100.
5 Cincinnati Literary Gazette, July 31, 1824.
6 Frances Trollope, Domestic Manners of the Americans (London, 1832), 114-5.
7 Anthony Trollope, Autobiography (New York, 1905), 156.
8 John P. Foote, The Schools of Cincinnati and Its Vicinity (Cincinnati, 1855), 64-5.
9 George M. Roe, Cincinnati: The Queen City of the West (Cincinnati, 1895), 360.
10 Report of the Special Committee ... on the Best Method of Obtaining a Complete Geological Survey of the State of Ohio (Columbus, 1836), 15.
11 Ohio Geological Survey, Second Annual Report on the Geological Survey of the State of Ohio (Columbus, 1838), 203.
12 Ibid., 211.
13 Ibid., plate facing p. 211.
14 Ibid., 206.
15 Nelson W. Evans and Emmons B. Stivers, A History of Adams County, Ohio ... (West Union, Ohio, 1900), 10.
16 Wright, Address on ... John Locke, 40.
17 Roc, Cincinnati, 360.
18 American Journal of Science, XLI (1841), 158ff.
19 Ibid., XLII (1842), 235, 366.
20 U. S. Congress, 26 Cong., 1 sess., Executive Document No. 239, pp. 53, 116-39.
22 American Association of Geologists and Naturalists, Abstract of the Proceedings, V (1844), passim.
23 American Journal of Science, n. s., VIII (1849), 233.
24 Ibid., 237-8.
25 Ibid., 241.
26 American Association for the Advancement of Science, Proceedings, V (1851), passim.
27 Ohio State Board of Agriculture, Ninth Annual Report ... 1854 (Columbus, 1855), 212-2.

Footnotes, on different pages in the original text, here all moved to gather at end of article. Text from Ohio History, Journal of the Ohio Historical Society (Oct-Dec 1946), 55, No. 4, 346-373. (source)


See also:
  • 19 Feb - short biography, births, deaths and events on date of Locke's birth.
  • John Locke's Electro-Chronograph - for automatic registration of time observations used in astronomical observatories.

Nature bears long with those who wrong her. She is patient under abuse. But when abuse has gone too far, when the time of reckoning finally comes, she is equally slow to be appeased and to turn away her wrath. (1882) -- Nathaniel Egleston, who was writing then about deforestation, but speaks equally well about the danger of climate change today.
Carl Sagan Thumbnail Carl Sagan: In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. (1987) ...(more by Sagan)

Albert Einstein: I used to wonder how it comes about that the electron is negative. Negative-positive—these are perfectly symmetric in physics. There is no reason whatever to prefer one to the other. Then why is the electron negative? I thought about this for a long time and at last all I could think was “It won the fight!” ...(more by Einstein)

Richard Feynman: It is the facts that matter, not the proofs. Physics can progress without the proofs, but we can't go on without the facts ... if the facts are right, then the proofs are a matter of playing around with the algebra correctly. ...(more by Feynman)
Quotations by: • Albert Einstein • Isaac Newton • Lord Kelvin • Charles Darwin • Srinivasa Ramanujan • Carl Sagan • Florence Nightingale • Thomas Edison • Aristotle • Marie Curie • Benjamin Franklin • Winston Churchill • Galileo Galilei • Sigmund Freud • Robert Bunsen • Louis Pasteur • Theodore Roosevelt • Abraham Lincoln • Ronald Reagan • Leonardo DaVinci • Michio Kaku • Karl Popper • Johann Goethe • Robert Oppenheimer • Charles Kettering  ... (more people)

Quotations about: • Atomic  Bomb • Biology • Chemistry • Deforestation • Engineering • Anatomy • Astronomy • Bacteria • Biochemistry • Botany • Conservation • Dinosaur • Environment • Fractal • Genetics • Geology • History of Science • Invention • Jupiter • Knowledge • Love • Mathematics • Measurement • Medicine • Natural Resource • Organic Chemistry • Physics • Physician • Quantum Theory • Research • Science and Art • Teacher • Technology • Universe • Volcano • Virus • Wind Power • Women Scientists • X-Rays • Youth • Zoology  ... (more topics)


- 100 -
Sophie Germain
Gertrude Elion
Ernest Rutherford
James Chadwick
Marcel Proust
William Harvey
Johann Goethe
John Keynes
Carl Gauss
Paul Feyerabend
- 90 -
Antoine Lavoisier
Lise Meitner
Charles Babbage
Ibn Khaldun
Euclid
Ralph Emerson
Robert Bunsen
Frederick Banting
Andre Ampere
Winston Churchill
- 80 -
John Locke
Bronislaw Malinowski
Bible
Thomas Huxley
Alessandro Volta
Erwin Schrodinger
Wilhelm Roentgen
Louis Pasteur
Bertrand Russell
Jean Lamarck
- 70 -
Samuel Morse
John Wheeler
Nicolaus Copernicus
Robert Fulton
Pierre Laplace
Humphry Davy
Thomas Edison
Lord Kelvin
Theodore Roosevelt
Carolus Linnaeus
- 60 -
Francis Galton
Linus Pauling
Immanuel Kant
Martin Fischer
Robert Boyle
Karl Popper
Paul Dirac
Avicenna
James Watson
William Shakespeare
- 50 -
Stephen Hawking
Niels Bohr
Nikola Tesla
Rachel Carson
Max Planck
Henry Adams
Richard Dawkins
Werner Heisenberg
Alfred Wegener
John Dalton
- 40 -
Pierre Fermat
Edward Wilson
Johannes Kepler
Gustave Eiffel
Giordano Bruno
JJ Thomson
Thomas Kuhn
Leonardo DaVinci
Archimedes
David Hume
- 30 -
Andreas Vesalius
Rudolf Virchow
Richard Feynman
James Hutton
Alexander Fleming
Emile Durkheim
Benjamin Franklin
Robert Oppenheimer
Robert Hooke
Charles Kettering
- 20 -
Carl Sagan
James Maxwell
Marie Curie
Rene Descartes
Francis Crick
Hippocrates
Michael Faraday
Srinivasa Ramanujan
Francis Bacon
Galileo Galilei
- 10 -
Aristotle
John Watson
Rosalind Franklin
Michio Kaku
Isaac Asimov
Charles Darwin
Sigmund Freud
Albert Einstein
Florence Nightingale
Isaac Newton



who invites your feedback
Thank you for sharing.
Today in Science History
Sign up for Newsletter
with quiz, quotes and more.