278 MANIPULATIOX. 



CHAPTER V. 



ON PRESERVATIVE FLUIDS. 



The preservative fluids, like the cements before described, 

 require to be varied according to the nature of the structures 

 they may be employed to conserve ; thus, for instance, a solu- 

 tion of salt, alum, and corrosive sublimate in water, that will 

 keep most fleshy substances, will destroy others that contain 

 bone ; hence it becomes necessary to select a diflferent fluid 

 for each of these structures, and of all the various kinds that 

 have hitherto been employed, with the single exception of 

 spirit, there is no one kind that is universally applicable; for 

 large preparations, proof spirit will answer every purpose ; 

 but as this is rather too strong for most of the cements used 

 by the microscopist, it has been ascertained that for all delicate 

 structures there are certain proportions of alcohol and distilled 

 water that will be sufficient to preserve them, and will not 

 act in any way either on the marine-glue, gold-size, or asphal- 

 tum. The following fluids will be found the most generally 

 useful. 



Spirit and Distilled Water. — In the proportion of one ounce 

 of alcohol 60° above proof, to five of distilled water, a fluid 

 may be made that is capable of preserving not only injections, 

 b^it the elementary tissues both of animals and vegetables, but 

 all the colours of the latter wiU be destroyed. 



Acetate of Alumina. — This, when dissolved in distilled water 

 in the proportion of one ounce of the former to four of the 

 latter, wiU preserve even very delicate colours, and when 

 injected into the blood vessels of animals. Is said to prevent 

 decomposition, and forms the so called Gannal process, em- 

 ployed very much on the Continent for the preservation of 

 animal structures on a large scale. 



Goadhy's Fluids. — The first of these, and the one for which 

 Mr. Goadby was rewarded by the Society of Arts, consists of 

 four ounces of bay salt, two ounces of alum, four grains of 

 corrosive sublimate, and two quarts of boiling water ; these 



