158 Mr. Davy’s Account of some analytical Experiments 
it gave a white precipitate when mixed with solution of oxalate 
of ammonia, and did not affect solution of prussiate of potash 
and iron. 
In the green opaque variety, calcareous earth was indicated 
by solution of oxalate of ammonia : and it contained oxide of 
manganese ; for it was not precipitated by solution of ammo- 
nia ; but was rendered turbid, and of a gray colour, by solution 
of prussiate of potash and iron. 
The residuum of the alkaline solution of the yellow variety, 
when dissolved in muriatic acid, produced a small quantity of 
white solid matter when mixed with the solution of the oxalate 
of ammonia, and gave a light yellow precipitate by exposure 
to ammonia ; but after this, when neutralized, it did not affect 
prussiate of potash and iron, so that its colouring matter, as 
there is every reason to believe, was oxide of iron, 
IV, Analysis of the Fossil . 
Eighty grains of the fossil consisting of the whitest and most 
transparent parts that could be obtained, were introduced into 
a small glass tube having a bulb of sufficient capacity to receive 
them with great ease. To the end of this tube, a small glass 
globe attached to another tube, communicating with a pneuma- 
tic mercurial apparatus, was joined by fusion by means of the 
blow- pipe. 
The bulb of the tube was exposed to the heat of an Argand 
lamp; and the globe was preserved cool by being placed in a 
vessel of cold water. In consequence of this arrangement, the 
fluid disengaged by the heat, became condensed, and no elastic 
matter could be lost. The process was continued for half an 
hour, when the glass tube was quite red. 
