CHEMICAL PHYSIOLOGY. 43 



of water. Its ash contains acid phosphates and a 

 quantity of free phosphoric acid, a residue of the 

 destroyed cerebric acid. Besides much potassium, 

 some sodium, little magnesium and calcium, the ash 

 always contains a notable quantity of iron. The ash 

 of the grey matter of the brain is always alkaline, 

 owing in part to the circumstance that it contains less 

 cerebric acid than the white matter. When an ethereal 

 extract of brain matter is mixed with water, and seen 

 under the microscope, it swells and projects various 

 peculiar forms of matter in various directions. The 

 phenomenon is due to cerebric acid, which is dissolved 

 in soap ; it has given much and varied amusement to 

 microscopists. 



The connective tissue forms tendons, fasciao org ctive 

 envelopes of muscles and limbs, ligaments of joints and 

 capsules, and binds all organs of the body together. 

 It consists of fibres, of a cement uniting these to a 

 tissue, of cells or so-called corpuscles, and is inter- 

 spersed with elastic fibres. It is soaked with potas- 

 sium-albumen. The cement is soluble in caustic lime Cement 

 and in baryta-water ; it is reprecipitated by acetic acid, 

 and then manifests itself as mucine, identical with that 

 of the salivary glands and embryonic tissues, e. g., the 

 umbilical cord ; the fibrillas remain isolated, but mixed 

 with the corpuscles or cells and their nuclei, and with 

 elastic fibres. In acetic acid the fibrillse are trans- 

 formed into glutine or glue. The same transformation 

 is effected by prolonged boiling in water. The elastic 

 fibres resist this treatment. Both sorts of fibre by 

 chemolysis yield tyrosine, leucine, volatile acids, and 



