74 
THE MICROSCOPE IN VETERINARY MEDICINE. 
The first observations were made upon the blood and l 3 mipli 
taken from a sheep affected with variola. In both fluids 
moving bodies were detected; even under the quarter-inch ob¬ 
jective minute specks and fine filaments were seen in a state 
of considerable activity. A higher power (-^V) was after¬ 
wards employed for the purpose of bringing into view the 
structure of the organisms^ and it was found that they were 
thus resolved into bacteria and vibriones. The specimen 
in which these bodies were most numerous was kept moist 
for a few days, and on being again examined with the ^’- 7 ^ 
of an inch glass was observed to contain large bacteria, some 
of them of a peculiar form; and besides the bodies previously 
observed, many infusoria were present. At page 667 of the 
for October, Fig. 9, the several bodies are depicted, 
excepting the animalcules, which possess no special interest, 
as they occur in all fluids which contain a small quantity of 
organic matter. 
No fungi nor spores of fungi were detected during the 
examination of lymph from a variolous vesicle and the blood 
of a diseased sheep; and the specimen figured at page 667, 
vol. xli, was therefore set aside in order that frequent examina¬ 
tions might be made, and any further development of organic 
bodies in the fluid at once discovered. The method pursued 
was very simple and perfectly effective, requiring so trifling 
an expenditure of time, that the experiments may easily be 
repeated by those whose professional occupations leaA-e them 
very little leisure to prosecute minute researches. 
First, the object was prepared in the ordinary way :—a 
drop of the fluid was placed in the centre of a clean glass 
slide, and covered with a piece of thin glass; if the is to 
be used the thinnest glass, prepared for the purpose, must be 
put over the specimen. The ordinary covering glass will not 
answer for anything above the one eighth of an inch objective. 
In the next place a few threads of cotton were loosely twisted 
together and placed across the glass slide in such a way that 
the cotton touched the edge of the covering glass, and hung 
down on each side for one or two inches; the slide was then 
placed over the opening of a small jar filled with distilled 
water, the ends of the cotton being left in the water. By 
capillary attraction the water will ascend on both sides, 
and keep the object in a moist condition for any length of 
time, if care is taken to supply the loss of water from the 
jar occasioned by the evaporation which is constantly 
going on. 
In this manner the specimen of variolous matter was 
treated, and at the same time a drop of milk and a portion of 
