Brain Preservation 387 



Reil's method of preparing the brain : * 



" Of the methods which I have employed in preparing brains 

 those contained in the following directions answer best : (i). 

 I<et the brain be hardened in alcohol and then placed in a so- 

 lution of carbonated or pure alkali, in the latter two days, in 

 the former for a longer period, and then again hardened in 

 alcohol if thus rendered too soft. The advantage of this 

 method is that the fasciculi of nervous matter are more readily 

 separable and the brown matter more distinguishable from the 

 white than after simple maceration in alcohol ; the gray mat- 

 ter is rendered by the alkali of a blacker gray and assumes the 

 consistence of jelly. (2). Let the brain be macerated in al- 

 cohol in which pure or carbonated potass, or ammonia, has 

 been previously dissolved ; the contraction of the brain is 

 lessened by this process. (3). L,et the brain be macerated in 

 alcohol from six to eight days and then its superficial dissec- 

 tion commenced, and the separation of the deeper parts con- 

 tinued, as the fluid in which the brain is kept immersed, pen- 

 etrates its substance. This method appears to me better than 

 the preceding, and would very likely be improved if the al- 

 cohol were rendered alkaline. The fibers in a brain thus pre- 

 pared are more tenacious than otherwise, and the deeper parts 

 are sooner exposed to the influence of the alcohol." 



These methods are applicable chiefly for the macroscopic 

 study of commissural relations and the general direction of 

 fibers. 



J. Miiller in 1834 recommended the use of creosote water 

 for the preservation of the brain and myel. 



Alcohol is the oldest and most universal preservative em- 

 ployed. It has good "fixing " properties but needs consider- 

 able attention in order to produce the best results. For fixing, 

 it is frequently used in conjunction with some of the various 

 salts, or in case some non-alcoholic fixer is used, it supple- 

 ments or completes the hardening thus begun. As a preserv- 

 ative it is generally used at the ordinary commercial strength 

 — ninety to ninety -five per cent., although for most tissues 

 eighty or even seventy-five per cent, seems to suffice. 



On account of the continuous dehydration and the struct- 



*Mayo's translation of Reil's Eighth Essay. 



