1816.) Linnean and Geological Societies. 807 
water. The three last salts are infusible. Apatite is found ready 
formed in the earth. Whenever a salt containing lime is decom- 
posed by a phosphate, osteo-phosphate of lime is always obtained. 
There are three combinations of phosphoric acid and potash, 
namely : 
Acid. Base. 
Phosphate composed of....+..+++++ 1 atom + 1 atom 
Biphosphate ..----- vir ited rts a wr +1 
Subphosphate ......++eeerereeee I +2 
There are two phosphates of soda. 
Acid. Base. 
Phosphate composed of .......... 2atoms + 1 atom 
Biphosphate .....+++> Ps Sos 4° + 1 
Ammonia resembles lime in its mode of combining with phos- 
phoric acid. 
The constituents of several other phosphates are given; but it 
would be tedious to detail the whole of them here. 
LINNZAN SOCIETY. 
On’ Tuesday the 5th of March a paper by Mr. Robert Brown, 
Librarian to the Society, was read, giving an account of some 
anomalies in the structure of seeds. A paper on this subject by 
Mr. Brown had been read to the Society in 1813, and was at that 
time withdrawn, in order to obtain an additional number of facts. 
The present paper consisted in some new facts respecting the struc- 
ture of naked seeds. According to the author, no seed exists with- 
out a covering ; but sometimes this covering bursts before the seed 
comes to maturity. He gave a particular account of the structure 
of the seed of the leontice thalictroides, which had been mistaken 
by preceding carpologists. 
On Tuesday the 19th of March a paper by Mr. Salisbury was 
read, on a natural family of plants, to which he gave the name of 
rodorace. He divided it into three orders ; namely, andromedee, 
ericee, and epacridee. ‘The paper contained a detail of the dif- 
ferent genera which constitute the order of andromedee. The 
author pointed out many new distinctions, which enabled him to 
subdivide several of the genera, and establish new genera. 
GEOLOGICAL SOCIETY. 
Jan. 5, 1816.—A communication from J. Taylor, Esq., M.G.S. 
on some remarkable appearances in coke, was read. 
The coke in question is produced from two varieties of New- 
castle coal, known in the market by the name of Tanfield Moor, 
and Pontop. The coal is charred in an oven of brick-work, of 
very simple construction, each charge being sufficient to cover the 
floor to the thickness of 18 or 20 inches; the combustion begins at 
the surface and proceeds gradually downwards. When all the 
bituminoys matter has been driven off, the mouth of the oven is 
