THEORIES AND EXPERIMENTS IN ANTISEPSIS. 
561 
when he noticed that the bacteria were apparently killed and 
the spores ceased to develop ; but on then inoculating guinea 
pigs with the apparently sterilized infusion, anthrax rapidly ap¬ 
peared, the animals died and the blood was swarming with the 
bacillus anthracis. He concludes that a solution of i-iooo, al¬ 
though it kills the non-spore-bearing organisms, only stupefies 
and does not destroy the spores of bacillus anthracis. Dr. 
Woodhead explains Klein’s result as due to the precipitation of 
the mercuric chloride by the albumen present, u which gave a 
coating or pellicle of albuminate of mercury round the spores, 
protecting them from further action uutil they were introduced 
into the blood of the animals, when the excess of albumen re¬ 
dissolved the pellicle and set the organism free to flourish in its 
new surroundings.” Koch has repeated his experiments and 
somewhat modified his earlier conclusions. He still affirms 
that mercuric salts, especially the chloride, are most valuable. 
“ For a ship’s bilge, where a 5$ solution of carbolic acid must 
be left for forty-eight hours, a 1-1000 mercuric chloride solution 
only required a few minutes.” He admits that u there is on 
the other hand reason for doubting the efficiency of this salt, for 
though anthrax spores subjected to a 1 in 20,000 solution for 
ten minutes and then washed in alcohol gave no growth in nu¬ 
trient gelatine, silk threads infected with the spores and then 
exposed for ten minutes to a 1 in 20,000 or even 1 in 10,000 
solution proved fatal to mice.” Herroun considers that the 
value of this substance as an antiseptic has been very much 
overrated, as he has cultivated ordinary septic bacteria in albu¬ 
minous filtrates containing 1 in 20,000 of mercuric chloride. 
u It is precipitated by albumens if used in greater strength, and 
is readily converted by the sulphur of all bodies into insoluble 
mercuric sulphide which is practically inert.” It may be re¬ 
marked also that mercuric chloride is precipitated by any alka¬ 
line solution such as ammonia, etc. Laplace in a series of 
experiments found that 5 cc. of blood serum was sufficient to 
precipitate the mercury from 5 cc. of a solution of the strength 
of 1 in 1000, but that by adding hydrochloric acid in the pro- 
