Louis Pasteur : his life and labours / by his son-in-law ; tr. from the French by Lady Claud Hamilton ; with an introduction by John Tyndall.

  • Vallery-Radot, René, 1853-1933.
Date:
1886
Catalogue details

Licence: Public Domain Mark

Credit: Louis Pasteur : his life and labours / by his son-in-law ; tr. from the French by Lady Claud Hamilton ; with an introduction by John Tyndall. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    which falls upon the leaf and fouls it. This is the excreta of the worms, which the microscope shows to be more or less filled with corpuscles drawn from the lining of the intestinal canal. It is there that they swarm. It is easy to understand that these excreta, falling on the leaves, contaminate them all the more easily because the worms, by the weight of their bodies in crawling, press the-excreta against the leaves. This is one cause of natural contagion. By the ex- creta of corpusculous worms which he crushed, mixed with water, and spread with a paint-brush over the mulberry leaves intended for a single meal, Pasteur was able to communicate the contagion to as many worms as he liked. He also indicated another natural and direct cause of contagion. The six fore-feet of the worm have sharp hooks at their ends, by means of which the worms prick each other's skins. Let any one imagine a healthy worm passing over the body of the corpus- culous worm. The hooks of the first worm, by pene- tratmg the skin of the second, are liable to be soiled by the corpuscles immediately below that skin; and these hooks are capable of carrying the seeds of dis- ease to other healthy worms, which may be pricked in their turn. To demonstrate experimentally, as Pas- teur did, the existence of this cause of contagion, it was only necessary to take some worms and allow them to wound each other. Lastly, infection at a