0. C. Marsh on the Remains of a new Enaliosaurian. 



Chemical examination of the eemains of the Eosaurus 



I cjiemical and a physiological point of view; 

 and has already attracted some attention. As it is desirable to 

 add to the limited amount of data on this subject hitherto col- 

 lected, the writer has analyzed a portion of a vertebra of the 

 Eosaurus, and the results obtained are given below. 



A preliminary qualitative examination of the fossils having 

 shown the presence of iron, manganese, copper, alumina, lime, 

 magnesia, potash, soda, organic matter, and water ; as well as 

 fluorine, chlorine, sulphur; silicic, carbonic, phosphoric and sul- 

 puric acids, the complete separation of these numerous constitu- 

 ents was necessarily attended with some difficulty. 



The following is a general outline of the methods employed in 

 the analysis : The finely powdered substance was first dried over 

 sulphuric acid, and then divided into several portions, between 

 one and two grammes each. One of these was fused with car- 

 bonate of soda ; and the resulting mass dissolved in dilute chlor- 

 hydric-acid; the solution was then evaporated to dryness in a 

 water bath, and the silicic acid present was separated and de- 

 termmed in the usual manner. From the filtrate which re- 

 mamed, the copper was precipitated by sulphuretted hydrogen ; 

 and, as the amount of this metal in the substance was small, the 

 precipitate was converted into oxyd of copper by moistening it 

 with ifitric acid, then ignited and weighed. The lime was next 

 separated from the remaining solution by sulphuric acid, in the 

 presence of an excess of alcohol, and determined as sulphate. 

 When the alcohol had been removed from the last filtrate by 

 evaporation, the organic matter destroyed and the manganese 

 oxydized by chlorate of potash, the solution was made alkaline 

 by ammonia, and the iron, manganese, alumina, magnesia, fluo- 

 rine,^ and part of the phosphoric acid present, were tluis precipi- 

 Ifter washing with ammonia water to prevent the s 



tion of the magnesia salt, the precipitate was dried, ignited and 

 weighed. To ensure the complete separation of the phosphoric 

 acid, a weighed portion of iron was converted into the sesqui- 

 chlorid, and added to the preceding filtrate ; the resulting phos- 

 phate of iron was then precipitated by ammonia; ignited, 

 weighed, and the amount added to the weight of the previous 

 precipitate. The two were then redissolved in chlorhydric acid, 

 and the phosphoric acid in the substance separated by molybdate 

 of ammonia. This precipitate was next redissolved in caustic 

 ammonia; the phosphoric acid again precipitated by the addi- 

 tion of sulphate of magnesia and chlorid of ammonium, and 

 finally determined in the form of basic phosphate of magnesia. 



