37 
Facts and Observations. 
VETERINARY MEDICINE IN SWITZERLAND. 
No person is allowed to practise the veterinary art in Switzer- 
land without a licence of the Council of State. This is granted 
after the passing of an examination. The Board of Health 
appoints the Board of Examiners, consisting of a doctor of 
medicine, a surgeon, a pharmacien, and two veterinary prac- 
titioners. The regulations respecting the examination, which 
is public and gratuitous, viva voce , and of two hours* duration, 
are similar to those adopted for other branches of the healing 
art ; the subjects selected being such as are appropriate to 
the veterinary profession. 
THE PREPARATION OF COLLODION FOR SURGICAL 
PURPOSES. 
f 
For this purpose, Hofmann introduces 1 part of cotton 
wool into a mixture consisting of 20 parts of the strongest 
nitric acid, and 30 parts of sulphuric acid, for a quarter of 
an hour. The operation should be conducted in a glass 
vessel with a cover, and the cotton stirred frequently by means 
of a glass rod. The cotton is then well washed, to remove 
the least trace of acid, and pressed strongly in a linen cloth,, 
and before being dried it should be pulled, to separate the 
knotty portions. The cotton should be now dried in a sieve 
over a stove. Six parts of the cotton thus prepared are dis- 
solved in a mixture of 120 parts of ether and 8 parts of rectL 
fied spirits of wine, to which 3 parts of castor oil are finally 
added. Hofmann states that this collodion does not crack or 
contract like that prepared in the usual manner. 
IODIDE OF POTASSIUM AS A TEST FOR OZONE. 
Cloez has shown by experiment that the ordinary test for 
ozone, the iodized starch, is unsuitable for the detection of 
ozone in the atmosphere. All the results obtained by these 
means he considers of no value, because the iodide of potas- 
