And this is the ultimate lesson that our knowledge of the mode of transmission of typhus has taught us: Man carries on his skin a parasite, the louse. Civilization rids him of it. Should man regress, should he allow himself to resemble a primitive beast, the louse begins to multiply again and treats man as he deserves, as a brute beast. This conclusion would have endeared itself to the warm heart of Alfred Nobel. My contribution to it makes me feel less unworthy of the honour which you have conferred upon me in his name.

Herewith I offer you the Omnipotent Finger of God in the anatomy of a louse: wherein you will find miracles heaped on miracles and will see the wisdom of God clearly manifested in a minute point.

I cannot but look upon the strange Instinct of this noisome and troublesome Creature a Louse, of searching out foul and nasty Clothes to harbor and breed in, as an Effect of divine Providence, design’d to deter Men and Women from Sluttishness and Sordidness.

The native hospital in Tunis was the focal point of my research. Often, when going to the hospital, I had to step over the bodies of typhus patients who were awaiting admission to the hospital and had fallen exhausted at the door. We had observed a certain phenomenon at the hospital, of which no one recognized the significance, and which drew my attention. In those days typhus patients were accommodated in the open medical wards. Before reaching the door of the wards they spread contagion. They transmitted the disease to the families that sheltered them, and doctors visiting them were also infected. The administrative staff admitting the patients, the personnel responsible for taking their clothes and linen, and the laundry staff were also contaminated. In spite of this, once admitted to the general ward the typhus patient did not contaminate any of the other patients, the nurses or the doctors. I took this observation as my guide. I asked myself what happened between the entrance to the hospital and the wards. This is what happened: the typhus patient was stripped of his clothes and linen, shaved and washed. The contagious agent was therefore something attached to his skin and clothing, something which soap and water could remove. It could only be the louse. It was the louse.

Whatever is Natural doth by that appear, adorned with all imaginable Elegance and Beauty. There are such inimitable gildings and embroideries in the smallest seeds of Plants, but especially in the parts of Animals, in the head or eye of a small Fly: such accurate order and symmetry in the frame of the most minute creatures, a Lowse or a Mite, as no man were able to conceive without seeing of them. Whereas the most curious works of Art, the sharpest finest Needle, doth appear as a blunt rough bar of iron, coming from the furnace or the forge. The most accurate engravings or embossments, seem such rude bungling deformed works, as if they had been done with a Mattock or a Trowel.

Ye ugly, creepin’, blastit wonner,
Detested, shunn’d by saunt an’ sinner!
How dare ye set your fit upon her,
Sae fine a lady?
Gae somewhere else, and seek your dinner
On some poor body.