in Rocks and Minerals. 



163 



The following is a list of the minerals which I examined for 

 phosphoric acid. I have also noticed those in which potash 

 and soda occur, that is, those rocks in which these substances 

 had not hitherto been noticed. 



Minerals. 

 Nine varieties of carbo- 

 niferous limestone from 

 the neighbourhood of 

 Cork. 



Muschelkalk and dolomitt 

 from the same forma^ 

 tion, from near Fulda in 

 Hesse-Casel. 



Roojing-slate used at 

 Giessen. 



Flags used in the west of 

 Ireland, supposed to be 

 millstone grit. 



Slate from Corrigaline, 

 near Cork. 



Old red sandstone, Cork. 



Phosphoric acid. 

 In all I could detect its 

 presence, and in one it 

 occurred in sufficient 

 quantity to be deter 

 mined. 



Present, but apparently 

 more abundant, in the 

 dolomite. 



Considerable precipitate, 

 but tvavellite is found in 

 some localities in the 

 same rock. 



Traces, but very minute, 



Precipitate large enough 

 to examine quantita- 

 tively. [This is the best 

 locality known, I be 

 lieve, for wavellite.j 



Trace in one specimen, 

 but a decided precipi- 

 tate was obtained from 

 three ounces of another. 



Alkalies. 



Potash was found present 

 in all, but in such small 

 quantity that I could 

 not determine it. From 

 the same cause I could 

 not determine whether 

 soda was present. 



Minute traces. 



Large precipitate, with 

 chloride of platinum 

 and a small trace of 

 soda. 



Trace of potash, but 

 could not ascertain if 

 soda was present. 



Decided precipitate with 

 chloride of platinum. 

 Sufficient soda to pro- 

 duce a precipitate with 

 antimoniate of potash. 



Could not detect soda, 

 but detected a trace of 

 potash. 



Minerals. 



Diorite containing augite, from the 

 valley of the Lahn, Nassau. 



Clinkstone, from Rhongebirge, Ba- 

 varia. 



Phonolitic Tufa, Rhongebirge, Ba- 

 varia. 



Hornblende in crystals, from Rhon- 

 gebirge. 



Olivine, in a state of decomposition, 

 from the Vogelsgebirge, Hesse- 

 Darmstadt. 



Augite, crystalline, Rhongebirge. 



Compact basalt, from Giessen. 



Trap rock of the nature of green- 

 stone, from the north of Ireland. 



Basalts, Giant's Causeway. 



Pumice stone, from the Lake of I^aach, 



near Andernach, on the Rhine. 



M 



Phosphoric acid. 

 Obtained sufficient from two ounces 

 to test with nitrate of silver. 

 Abundant traces. 



Considerable precipitate. 



Minute traces. 



Sufficient to ap])Iy the test of nitrate 

 of silver; but three ounces were 

 employed. 



Abundant traces. 



Considerable traces. 



Only minute traces in one specimen, 

 but in considerable quantity in an- 

 other. 



Enough to produce a precipitate 

 with sulphate of ammonia and mag- 

 nc<\a. from two ounces. 



Considerable precipitate from three 

 ounces. 



2 



