702 



THE MICROSCOPE. 



then allows it to remain a few hours in turpentine, or 

 until the nerves are seen to be white and shining, when 

 they are ready for cutting into perpendicular sections with 

 the double (Valentine's) knife. 



It is proposed to employ chloride of gold to stain the 

 tissues of the body. Tissues soaked in a weak solution 

 of from one to two per cent, of this salt in distilled w^ater, 

 and afterwards exposed to light, are found to exhibit 

 certain parts, as nerve-fibres, connective tissue, corpuscles, 

 and cells generally, stained of violet-red colour, while 

 other parts, as intercellular substance, &c. are left un- 

 touched." The soaking must be continued until the tissue 

 assumes a straw-yellow colour, then taken out of the solu- 

 tion and placed in dilute acetic acid of one to two per 

 cent. The colour will be seen to gradually develop itself, 

 and Xolliker and Cohnheim, who have tried it, say that 

 nerve-fibre, &c. are exceedingly well shown in this way. 



Consolidated Tissues. — Such tissues are formed by a 

 chemical combination with the albumen and gelatine of 



the fibre ; this in cartilaginous 

 formations is termed chondrine, 

 the cells of which become con- 

 solidated by calcareous deposits, 

 and a gradual transition results 

 therefrom. Cartilage is the 

 firmest structare next to bone 

 met with ; it is ver}'- elastic, 

 and, as an intercellular sub- 

 fM^S%W)fM^ii^^kM^WWMM stance, is generally divided into 



two kinds. Between the ribs 

 we find this substance presentin 

 a uniform bluish appearance. 

 Fig. 'ii-2.— Cartilage, from ear of and slightly grauular ; tliis is 



Mouse, reseiubliu;.? a section of , \ •, , -i riii 



vegetr.l)le tissue, wiUi superim- 1^6, Or whltc Cartilage. The 



posed layers. otlier form of iuterceUular sub- 



stance is developed in fibrous substances ; and it is in 

 this peculiarly-formed felt- work that cells with nuclei are 

 found. This is known as yellow, fibrous, or spongy car- 

 tilage, the yellow colour depending on the mode of fitu'ous 

 arrangement of the intercellular substance : it is found in 

 the ears, and other parts. 



if 



o 



