164 Analysis of Coprolites. 



time. The house in which the lattter observations were made, is about 30 feet above 

 the level of the sea, and they were taken at 8 a. m., noon, and 8 p. m. The parti- 

 culars of those of 1781-82 are not given, but they were probably made in a similar 

 situation. 



My own observations in 1821 were made in various parts of the islands, and at 

 elevations varying from to 70 feet above the sea. The morning observations were 

 principally made at 8 a.m. ; the evening at various hours, between 9 and 12, but 

 chiefly between 9 and 10 r. Ji. 



Added to the mean of the morning and evening observations, to obtain the mean 

 of the day for the months of January, February 1799, 1 „ ^„ 



November and December 1798, j 

 March, April, May, 1799, . . . .1.39 



June 1799, 0.76 



July 1799, 1.14 



August 1799 0.82 



Analysis of Coprolites. By Dr William Gregory and Mr 

 R. Walker.* (Communicated by the Authors), 



1. Analysis of a Coprolite from BurdieJiouse. 



This coprolite was enclosed in a rolled mass of clay ironstone, 

 and the interior of the coprolite, when broken up, seemed to 

 have been converted into the same substance as that by which 

 it was surrounded. A good deal of pyrites (iron) was also 

 disseminated in the mineral. Owing to the small size of this 

 coprolite, and its mixture with foreign matter, its analysis was 

 rendered unusually difficult, and the proportion of phosphate of 

 lime was less than usual from the same cause. It would be 

 very desirable to have an opportunity of repeating the analysis, 

 on a larger portion of coprolite from the same locality. 



The result of our analysis is as follows : — 



1 



Organic matter, 



Sulphuret of iron, J- 4.134 



Siliceous matter, 



Carbonate of lime, G 1.000 



Carbonate of magnesia, 13.568 



Oxide of iron with a little alumina, C.400 



Phosphate of lime, 9.576 



Fluoride of calcium, ) . ^ 



rs -A e I A trace. 



Oxide or manganese, i 



Water and loss, 5.332 



100.000 



• Read before the Wernerian Natural History Society, 2,9th November and 

 13th December 1(!34. 



