82 THE LIFE OF PASTEUR 



terra nenn journeys in the immediate neighbourhood of graves, 

 bring back with them splenic spores, and thus scatter the germs 

 so exhumed? That would again be a singular revelation, un- 

 expected but quite simple, due to the germ theory. He wasted 

 no time in dreaming of the possibilities opened by that precon- 

 ceived idea, but, with lus usual impatience to get at the truth, 

 decided to proceed to experiment. 



On his return to Paris Pasteur spoke to Bouley of this pos- 

 sible part of germ carriers played by earthworms, and Bouley 

 caused some to be gathered which had appeared on the surface 

 of pita where animals dead of splenic fever had been buried 

 soni' years before. Villemin and Davaine were invited as well 

 as Bouley to come to the laboratory and see the bodies of these 

 worms opened ; anthrax spores were found in the earth cylinders 

 which filled their intestinal tube. 



At the time when Pasteur revealed this pathogenic action 

 of the earthworm, Darwin, in his last book, was expounding 

 their share in agriculture. He too, with his deep attention and 

 force of method, able to discover the hidden importance of what 

 seemed of little account to second-rate minds, had seen how 

 earthworms open their tunnels, and how, by turning over the 

 soil, and by bringing so many particles up to the surface by 

 tlnir " castings," they ventilate and drain the soil, and, by 

 their incessant and continuous work, render great bi - to 



agriculture. These excellent labourers are redoubtable grave- 

 diggers ; each of those two tasks, the one beneficent and the 

 other full of perils, was brought to light by Pasteur and Darwin, 

 unknowingly to each other. 



ir had gathered earth from the pits where splenic cows 

 had been buried in July, 1878, in the Jura. " At three different 

 tunes within those two years," he said to the Academie des 

 Sciences and to the Academie de Medecine in July, 1880, " the 

 surface soil of those same pits has pn sented charbon spores." 

 This fact had been continued by recent experiments on Ihl 

 soil of the Beaace farm; particles of earth from other parts 

 of the field had no power of provoking splenic fever. 



Pasteur, going on to practical advice, showed how grazing 

 animals might find in certain places the germs of charbon, 

 freed by the loosening by rain of the little castings of earth- 

 worms. Animals are wont to choose the surface of the pits, 

 where the soil, being richer in humus, produces thicker growth, 



