126 PREPARATION AND MOUNTING 



"white of an egg, well beaten, and again boil, until the albu- 

 men coagulates. Strain whilst hot through flannel, and 

 add an equal portion by measurement of Bowyer's pure 

 glycerine, and fifty drops of carbolic acid in solution ; boil 

 again for ten or fifteen minutes, and again strain through 

 flannel, place in a water-bath and evaporate to about one- 

 half, then filter into two or more broad-mouthed vials. (Cotton 

 is the best filtering medium.) The use of this in mounting 

 is the same as Mr. Lawrance's, elsewhere described. 



GOADBY'S FLUID. This is much used in the preservation 

 of animal objects ; and seldom, if ever, acts upon the colours. 

 It is thus prepared: Bay salt, 4 oz.; alum, 2 oz.; corrosive 

 sublimate, 4 grains. Dissolve these in two quarts of boiling 

 water, and filter. For delicate preparations some recom- 

 mend that this mixture be reduced by the addition of an 

 qual quantity of water ; but where there is bone or shell in 

 the object, the above acts injuriously upon it, in which case 

 this fluid may be used : Bay salt, 8 oz. ; corrosive subli- 

 mate, 2 grains ; water, 1 quart. 



THWAITES'S LIQUID. This is recommended for the preser- 

 vation of Algae, &c., as having little or no action on the 

 colour, and is thus prepared : Take one part of rectified 

 spirit, add drops of creosote enough to saturate it; to this 

 add sixteen parts of distilled water and a little prepared 

 chalk, and filter. When filtered, mix with an equal quantity 

 of camphor-water (as before mentioned), and strain through 

 fine muslin before using. 



CHLORIDE OF ZINC SOLUTION. In the Micrographic Dic- 

 tionary this is stated to be " perhaps the best preservative 

 known for animal tissues." Persons of great experience, 

 however, have given a very different opinion ; but it is cer- 

 tainly very useful in many cases where a small degree of 

 coagulating action is not injurious. It is used of strengths 

 varying according to the softness of the parts to be pre- 

 served ; the average being 20 grains of the fused chloride to 

 1 oz. of distilled water. To keep this liquid, a lump of cam- 

 phor may be left floating in the bottle. I have heard com- 



