254 ANNUAL OF SCIENTIFIC DISCOVERY. 



a current of air was passed through a solution of normal salified 

 albumen, sufficiently dilute not to allow of the froth passing out of 

 the vessel. This froth was seen- to be transformed into a solid 

 body insoluble in ammonia, potassa, water, or dilute acids. To 

 obviate two objections which might be started to this experiment, 

 air saturated with the vapor of water, and hydrogen purified by 

 caustic potassa and saturated with vapor, were successively employed. 

 Lastly, to avoid all sources of error, a solution of albumen diluted 

 with water was agitated in vacuo by converting the vessel into a 

 sort of water hammer, after expelling the air by heat and an air- 

 pump, the orifice being subsequently hermetically sealed. The 

 solution, perfectly limpid at first, became troubled after a few agita- 

 tions, and a membrane was rapidly formed." 



The solid bodies thus formed from a limpid solution of albumen 

 by the simple effect of agitation, have been subjected to microsco- 

 pic examination of M. Gluge, from whose report we make the 

 following extracts : " The albumen of the white of an egg, soli- 

 dified by mechanical actions resembles false membranes, and even 

 serous. It is presented to our view under the form of membranes 

 covered with granulations from one-half to one millimetre, in diame- 

 ter, white semi-transparent, about one-fourl.h or one-half millimetre 

 thick, and sufficiently elastic. With a magnifying power of three 

 hundred we can distinguish an amorphous substance, finely punctuated, 

 in which are found fibres, sometimes isolated, sometimes united iri 

 bundles like the fibres of cellular tissue, more often easily isolated and 

 elastic. More rarely there may be seen large and transparent fibres, 

 analogous to those which are met with in fibrin e. In the middle of 

 these fibrous bundles may be observed granulations composed of little 

 globules of 1-400 to 1-800 of a millimetre in size, and enclosing some 

 bubbles of air. These globules are sometimes very regularly grouped 

 and then form rounded masses." 



Dr. Lyons who has carefully examined a specimen of albuminous 

 membrane prepared by M. Melsens, with a high magnifying power, 

 says : " The granular base constituted a very considerable portion 

 of the entire specimen, but did not appear to be uniformly disposed 

 throughout it, as in some portions it formed nearly the entire, while in 

 others it was almost altogether replaced by fibres. The solidifying 

 force would thus appear not to have acted with uniformity. To deter- 

 mine what modifications of it produced granular matter what fibres 

 what again caused the formation of the little spherical bodies are 

 questions, perhaps, of too delicate a nature to admit of ready solution. 

 Could we arrive even at an approximate explanation, a great step 

 would be achieved in the history of the obscure process of histogenesis. 

 The most interesting of all the structures observable in this prepara- 

 tion are the spherical bodies. They are nearly uniform in size, 

 grouped quite close to each other, and present nearly uniform 

 characters. Under all conditions of light, both as to intensity and 

 obliquety, they presented a sort of nucleus, which in all Avas of a long 

 elliptical shape, although the bodies themselves appeared as nearly as 



