42 - REPORT—1846, 
He next examined the effects of the red prussiates; and here again, contrary to 
what would have been surmised from the want of action in the preceding compounds, 
it was found that they constituted a class almost as poisonous as the simple cyanides. 
The experiments were made with the red prussiates of potash and lead, and with a 
crystalline acid obtained by the action of muriatic acid and ether upon the former 
of these compounds. Each of them was quickly fatal in doses of from ten to forty 
grains. 
On the use of stating, with the results of Analyses, the nature of the Methods 
employed. By W. West, F.R.S. 
The author of this communication pointed out the necessity which existed for 
knowing, not merely the results to which chemists might arrive, but the processes 
by which these results were obtained. It was shown that many of the discrepancies 
found to exist in analytical results would thus be satisfactorily explained, and all 
doubt as to the correctness of an analysis removed. 
On the presence of Atmospheric Air, uncombined Chlorine, and Carbonic Acid 
found in the Water of some of the Wells in the suburbs of Southampton, 
and their Action on Lead. By Henry Osporn. 
The principal object of this paper was to caution persons residing in the neigh- 
bourhood of Southampton against the use of leaden pipes for conveying water, and 
to induce them to avoid the use of lead in any form for that purpose without having 
the water previously examined, in order to ascertain whether it possessed the property 
of acting upon the metal and holding it in solution. The author brought forward 
several instances of the serious consequences which had resulted from the use of 
water impregnated with lead, and pointed out the different solvent principles found 
in the water, one of which was uncombined chlorine discovered in a spring in the 
New Forest. This water possessed the property of bleaching Brazil paper and redden- 
ing litmus paper after concentration. The amount of uncombined chlorine was esti- 
mated as chloride of silver by deducting the amount of the latter contained in twenty 
ounces of water from that of the chlorine contained in the solid contents, the former 
weighing 1°2 more than the latter; thus indicating 0°296 of uncombined chlorine 
which is capable of uniting with 0°864 of lead, forming 1°16 of chloride of lead in 
the imperial pint. The lead held in solution by carbonic acid and the oxygen of 
atmospheric air was converted into chromate of lead, and estimated as chloride of 
lead, which indicated 0°25 or 0*2 of the oxide in twenty ounces of water. The solid 
contents in an imperial pint were found to vary from one to three grains, and to be 
composed of the chlorides of sodium, calcium and magnesia, sulphate of lime, silica 
and vegetable matter. Notwithstanding the preservative property which the salts 
contained in spring-water are said to possess by forming an insoluble crust in the 
interior of the pipes, it was found that the leaden pipes had been in use for some 
years and the action of the water on the lead still continued with as much energy as 
when they were first laid down, thus showing the presence of the above solvents, and 
that they met with no resistance from the presence of the saline matter. 
On the Rationale of certain Practices employed in Agriculture. 
By Prof. Dauseny, M.D., FBS. 
The Professor instanced among other practices the use of quicklime and of gypsum 
as fertilizers to the land. 
The former of these substances he supposes to act in part by rendering those in- 
organic substances which are present in the soil more soluble, or, in accordance with 
the views laid down by the author in a memoir which he has published in the Phi- 
losophical Transactions of last year, by converting the dormant constituents of the 
soil into active ones, or into a state in which they become immediately available. 
He appealed to the authority of Professor Fuchs, confirmed by that of Mr. Pri- 
deaux of Plymouth, as showing that the alkali may be extracted from granite readily 
by water after the rock in a pounded form has been heated together with quicklime ; 
