1871.] Dr. Marcet on the Constitution of Blood. 



465 



These appear to me to be the results of the present investigations : they 

 are still incomplete as to the crystalline forms of dechenite ; I would, 

 however, congratulate myself if the hints given in their exposition could 

 provoke further search for distinctly crystallized groups of dechenite. 



Contents. 



§ 1. Paragenetic relations of eosite. 

 § 2. Chemical characters of eosite. 

 § 3. Chemical properties of the chromo-walfenites. 



§ 4. Chemical properties of the vanadates of lead (dechenite, descloizite, and 



vanadite). 

 § 5. Crystallographical form of eosite. 

 § 6. Crystallographical forms of descloizite and vanadinite. 

 § 7. Crystallographical form of the chromo-walfenites. 

 1 8. Discussion of results. 



May 11, 1871. 



General Sir EDWARD SABINE, K.C.B., President, in the Chair. 



The following communications were read : — 



I. "An Experimental Inquiry into the Constitution of Blood and 

 the Nutrition of Muscular Tissue." By William Marcet, 

 M.D., F.R.S., Senior Assistant Physician to the Hospital for 

 Consumption and Diseases of the Chest, Brompton. Received 

 April 1, 1871. 



(Abstract.) 



The results obtained from the inquiry which forms the subject of the 

 paper are as follows : — 



First. That blood is strictly a colloid fluid. 



Second. That although blood be strictly a colloid, it contains invariably 

 a small proportion of diffusible constituents amounting to nearly 7*3 grms. 

 in 1000 of blood, and 9*25 grms. in an equal volume of serum, these 

 proportions diffusing out of blood in twenty-four hours. 



Third. That the proportion of chlorine contained in blood has a remark- 

 able degree of fixity, a fact which had been foreseen by Liebig, and may be 

 considered as amounting to 3 parts (the correct mean being 3"0f>) in 1000, 

 the proportion of chlorine in a bulk of serum equal to that occupied by 

 1000 grms. of blood being 3*45, and therefore higher than in blood, 

 and moreover that one of the objects of the chlorides, and other diffusible 

 constituents of blood, appears to be to preserve the fluid state of the blood. 

 The substances which yield an alkaline reaction to blood are mostly crys- 

 talloid ; their being retained in the blood while circulating through the 

 body must be of the highest importance in connexion with the phenomena 

 of oxidation constantly in progress during life. 



