TRANSACTIONS OF THE SECTIONS. 51 
which this extraordinary result does actually ensue; he now drew attention to the 
fact that it invariably occurs, and showed that the reasoning applied equally to cases 
in which the salt MR’ is not insoluble in water, but only less soluble than MR 
or HR’. 
Experiment confirmed this view; thus, among other instances, a saturated solution 
of sulphate of silver in aqueous nitric acid gives a crystalline deposit of the sparingly 
soluble sulphate, if it be treated with a strong solution of either nitrate of silver or 
sulphuric acid. Observations on the crystals that separate from solutions of sulphate 
of soda, or of nitrate of potash, in hydrochloric acid, when similarly treated, showed at 
once the influence of mass, and confirmed the conclusion that at all times four com- 
pounds coexist in the solution. The author's experiments on sparingly soluble salts 
dissolved in acids had all indicated that the law of reciprocal decomposition holds 
good in such cases also, and had afforded additional support to the inference, that 
if an acid HR dissolve a salt MR! to saturation, the addition of either MR or HR! 
will cause the production of more MR! than the acid can keep in solution, and which 
must accordingly precipitate or crystallize out. 
The former experiment of dissolving ferric phosphate in hydrochloric acid had 
been tried in absolute alcohol instead of water, with a still greater indication of the 
non-conversion of the whole of the iron into the state of chloride, and an equally 
clear optical demonstration that the addition of more hydrochloric acid increased the 
amount of ferric chloride present. 
On a remarkable Deposit of Carbonate of Lime about Fossils in the Lower 
Lias of Dorsetshire. By Grorce Guapstong, F.C.S. 
‘The object of this paper was to bring before the Section some very curious speci- 
mens of fibrous carbonate of lime, which the author found during a recent visit to 
Lyme Regis. 
The lower lias shales, which are there very fully developed, are in many instances 
parted by bands of fibrous carbonate of lime, some of which are less than a quarter of 
an inch thick, while others are several inches in thickness: the fibre runs exactly at 
right angles to the surface of the bands, through the middle of which a dividing line 
generally runs, as if the deposit has originated on both the upper and under sides 
simultaneously and met in the centre. 
In some places these bands are full of what appear like ammonites, having the 
markings perfect on both sides, and standing in high relief, as if they were the actual 
shells. On examining them minutely, however, it is found that they are composed 
merely of two layers of this fibrous carbonate of lime with the shell of the ammonite in 
a crushed and flattened state in the centre, the fibre of the lime still maintaining the 
same direction as in the rest of the band, viz."perpendicular to the flattened shell, and 
varying in length so as to preserve all the curves and ridges which the shell had when 
erfect. In one specimen, where the outer whorl of the ammonite being of stronger 
exture and filled with sediment, had not been crushed, the same deposit appears, 
forming a complete fringe of even thickness, and thus preserving all the form of the 
shell beneath. 
Some other shells exhibited the same curious appearance, but they are much less 
numerous than the ammonites, which must have swarmed at the time these beds 
were deposited. 
On the Alkaline Waters of Leeds. By W. Huaceon. 
The author gave the results of an analysis of a gallon of water from Ripley’s 
Well, Holbeck. ‘This aikaline water appears to contain a larger amount of alkaline 
matter than any in England. The nearest approach to it is the water of the artesian 
well in Trafalgar Square, which, according to the analysis of Abel and Rowney, con- 
tains 18 grains of carbonate of soda in the gallon, and 20 grains of the whole solid 
matter is chloride of sodium. 
_ I have examined ten of the alkaline waters of Leeds, and found them to vary in 
the quantity of carbonate of soda, “which is the alkaline substance they contain,” 
~ from 24 grains to 45 grains per gallon of water. 
4% 
