250 



Dr. G. Thin. 



1. The hairs when extracted were placed for a short interval in 

 potash solution (the strength used varied from 5 to 20 per cent.) ; 

 they were then washed in distilled water, and passed successively 

 through absolute alcohol and ether. After being thoroughly subjected 

 to the action of ether they were again placed successively in alcohol 

 and distilled water, and were then finally mounted for examination in 

 diluted Goadby's solution.* 



The object of these manoeuvres was to make the hair transparent, 

 free it from oily particles, and finally mount it in a medium suitable 

 for the detection and preservation of any organisms which it might 

 contain. The method was not perfectly nor always successful, but in 

 some instances it sufficed to show objects within the cuticle of the 

 hair, which I believe it is justifiable to consider as bacteria. 



2. The extracted hairs were at once examined in the Goadby's 

 solution. 



3. The hairs were placed successively in absolute alcohol, oil of 

 cloves, and dammar varnish, in which they were examined. 



4. Hairs kept for future examination in Goadby's solution, and in a 

 5 per cent, solution of carbolic acid were at convenient times, after 

 being soaked for a little while in distilled water, subjected to the 

 alcohol, oil of cloves, and dammar process. 



In all cases precautions were taken to prevent the development 

 of organisms after the hairs were extracted. 



Attempts to show the presence of bacteria in the hairs by staining 

 with methylaniline were defeated by the intensity with which the 

 hair itself was stained with this dye. 



The result of the examinations of a large number of hairs prepared 

 by these methods has been to satisfy me that minute objects can be de- 

 tected in them similar in size and form to those which I had recognised 

 as organisms on the borders of freshly-extracted hairs, and preparations 

 were obtained in which these objects were found in positions, and so 

 arranged as to show that they were distinct from the rows and aggre- 

 gations of minute granules which are found in healthy hairs. 



The objects referred to were seen either as round or as elongated 

 rounded bodies, and resembled in shape and in their refractive 

 qualities the elements which I have described as cocci in a paper 

 on Bacterium foetidum (" Proc. Roy. Soc," No. 205, 1880). In the 

 preparations put up in dammar varnish these bodies were not liable to 

 be mistaken for oily particles or crystals, which were not present in 

 the hairs. In the preparations put up in Goadby's solution, in spite 

 of the care which had been taken to soak the hairs in ether, oily 



* The following is the formula : — Bay salt, 12 ounces ; burnt alum, 6 ounces ; 

 corrosive sublimate, 15 grains ; water, 1 gallon. Dissolve and filter. I have found 

 it an excellent medium for mounting. 



