A RESUME OF THE USES OF FORMALIN. 69 



Fish makes objection to the use of formahn as a permanent 

 preservative on account of the large amount of water present, 

 which might cause freezing, and advises the addition of an equal 

 volume of alcohol. Hodenpyl,"*' in using formalin for making 

 sections on the freezing microtome (see below), found that the 

 least trace of formalin left in the specimen prevents it freezing. It 

 would therefore seem that Fish's objection is not valid. 



Koehler and Lumi^re found that if from fifty to a hundred and 

 fifty cubic centimetres of a solution of one volume of formalin, 

 diluted with four volumes of water, were injected into the gastro- 

 intestinal canal of small animals by the mouth and anus, also into 

 the carotid artery, and the animal was kept hung up in the air, in 

 a dry place, for some weeks, it was perfectly preserved without 

 distortion. They performed an autopsy on an animal — a guinea 

 pig — treated in this manner four months after, and found the 

 tissues and organs perfectly preserved. Dr. Henry Power* has 

 treated the bodies of children in a manner similar to this with 

 good results. Professor George S. Huntington informs me that 

 he has used formalin for the preservation of organs. He injects 

 a solution of from two to twenty-five per cent, into the blood- 

 vessels, and the result is a perfect preservation of the form and 

 colour of the organ. He has found that it is of no use for 

 preserving dissecting material. 



For the preservation of brains, formalin has given excellent 

 results. The fresh brain is placed in a ten per cent, solution, and 

 at the end of ten days it will have sufficiently hardened to permit 

 of the making of thick sections for demonstration of the gross 

 anatomy, the distinction between the white and grey matter being 

 more sharply defined than when alcohol is used. 



Parker and Floyd confirm the observations of Lanzilotti-Buon- 

 santi, Hoyer, Hoffer, and others, in regard to the swelling of the 

 brain when formalin alone is used. In a sheep's brain they found 

 this swelling to be forty per cent, of its original volume. In order 

 to correct this defect they experimented with various reagents in 

 combination with formalin. They finally found that a mixture of 

 six volumes of ninety-five per cent, alcohol and four volumes of a 



* Personal communication. 



