58 IIONV TO WORK 



very slight heat is sufficient to render it perfectly fluid. The gelatine 

 and glycerine, prepared by Mr. Rimmington, operative chemist, of 

 Bradford, is the best medium of the kind I have used. It may be 

 obtained by small bottles free by post for is. $d. 



107. Gum and Glycerine. Mr. Farrants has suggested the follow- 

 ing valuable preservative medium which will be found most useful for 

 mounting very many objects : 



Picked gum-arabic .. ... 4 ounces by weight. 

 Distilled water ... 4 



Glycerine .. ... ... 2 ,, 



It is to be kept in a stoppered bottle and a piece of camphor 

 added to the solution. 



108. Goaduy's Solution. This is made of several different 

 strengths. That most generally useful is the following : 



Bay salt ... ... ... ... 4 ounces. 



Alum ... ... ... ... 2 ounces. 



Corrosive sublimate. ... ... 4 grains. 



Boiling water ... ... ... 4 pints. 



Mix and filter. This solution for most purposes may be diluted 

 with an equal bulk of water. For preserving delicate preparations 

 it should be even still more dilute. Goadby's solution is very 

 valuable for preserving many anatomical specimens, but as it tends 

 to render tissues hard and opaque, is is not adapted for the preser- 

 vation of many structures which are to be examined in the microscope. 



109. Burnett's Solution, consisting of chloride of zinc, is a 

 powerful antiseptic, but not adapted for the preservation of micro- 

 scopical specimens. 



no. Chloride of Calcium. A saturated aqueous solution of 

 chloride of calcium, free from iron, has been much recommended 

 for preserving specimens of bone, hair, teeth, and other hard 

 structures, as well as many vegetable tissues. A solution of chloride 

 of calcium has been used by the late Professor Schroder Van der 

 Kolk, of Utrecht, for keeping sections of the spinal cord and pre- 

 parations of nerves. Many of these, through the kindness of my 

 friend, I have had an opportunity of seeing and can testify to their 

 excellence. 



ill. Alum ami other Salts. A solution of alum in the propor- 

 tion of one part of alum to sixteen of water has been found to 

 answer pretty well for some substances. Gannal's solution, which 

 consists of one part of acetate of alumina dissolved in ten parts of 

 water ; solutions of common salt (one part to five of water, with a 



