348 



Analysis of Lime. 



Vol. IV. 



now in progress in the laboratory of the 

 survey, establish the fact, that nearly all the 

 limestone belts in the south-eastern district 

 of the state, includinsr also those of the 

 Kittaning valley, contain bands of magne- 

 sian limestone capable of furnishing an hy- 

 draulic cement, identical in properties with 

 that so extensively manufactured in New 

 York, and on the Potomac, near Shepherds- 

 town." 



Now, when it is recollected that magne- 

 sia requires nearly eight thousand times its 

 weight of water to hold it in solution, would 

 it not seem that its unpness for the purposes 

 of agriculture is in proportion to its j?/«ess for 

 that of forming an hydraulic cement " of 

 great value?" Admitting, however, that the 

 question of the injurious nature of magnesia 

 to vegetation is not fully settled, yet, as no 

 one has ever supposed it valuable on this ac- 

 count, the fact is most decisive and very 

 striking, that in limestone containing 41 per 

 cent, of magnesia, there is a clear loss of 

 about one half in the quantity, when com- 

 pared with that which yields 96 per cent, of 

 carbonate, besides the cost of carriage of, to 

 say the least, a valueless article — a monstrous 

 difference, which one would suppose, will 

 be sufficient to induce farmers in every part 

 of the state to take the matter into their se- 

 rious consideration. 



In the Cabinet for April, there are no less 

 than three instances recorded of the injurious 

 effects of lime on vegetation, and these too, 

 from the testimony of practical men of high 

 standing and character — now, is it possible, 

 that such discrepancy could arise from either 

 the mode of using it, the season when it was 

 applied, or even to the quantity per acre? 

 I should rather believe it was owing to the 

 impurity of the lime — the magnesia contained 

 in its composition, and I will tell you why I 

 so believe : — I have often seen lime from a 

 neighbouring quarry, which I have remarked 

 required a great length of time to slack ; 

 and although this lime has not been carried 

 abroad until that operation had been com- 

 pletely effected, yet, wherever the heaps 

 have been deposited and suffered to remain a 

 while, all vegetation has ceased for the re- 

 mainder of the season on these spots, al- 

 though the greatest care imaginable had 

 been taken to remove every particle of lime 

 when carrying abroad : while the lime from 

 another quarry, not a mile distant, but from 

 the other side of the valley, obtained too at 

 the same season of the year, and applied in 

 the same quantity, and under the same cir- 

 cumstances, would be found to slack in a 

 very short time, and on the removal of the 

 heaps, although the same care to clear away 

 every portion had not been observed, yet 

 vegetation would be found immediately to 



go forward, and prove by its luxuriance that 

 much benefit, instead of injury, had been 

 derived from the application — nay, the her- 

 bage would spring up through the sides of 

 the heaps of lime, some inches in thickness, 

 while lying in process of slacking, and the 

 cattle would prefer this herbage to that which 

 grew by its side, without the aid of lime. 

 And on mentioning this circumstance to an 

 intelligent friend, he said, that he had ap- 

 plied this kind of lime to land before the 

 process of slacking had been completely 

 effected, and had observed lumps of it seve- 

 ral inches in thickness, which had been 

 spread abroad, and through which the oats 

 had sprung up, to the height of about five 

 feet, of the greatest luxuriance. 



Now, on examination at those quarries 

 and lime-kilns, I have found that the lime 

 which was injurious in its application to 

 land, would remain for a long time unslacked 

 in the kiln, after the fire had been extin- 

 guished ; while, in two days after the fire 

 had gone out in the other kiln, the lime 

 would begin to fall from the action of the 

 atmosphere alone, and this difference is uni- 

 formly observable.* And another remark- 

 able circumstance is, the limestone of the 

 hard quarry is much the heaviest before cal- 

 cination, but afterwards it is lighter than the 

 lime obtained from the calcination of the 

 stones of the soft quarry, which also yields 

 a larger quantity of slacked lime, and this 

 fact is known and acknowledged by every 

 one in the neighbourhood. We learn from 

 chemistry that magnesia, in the form of ep- 

 som salts, is chiefly procured from the mo- 

 thers, or residuum, which is found after the 

 separation of common salt from sea-water ; 

 and I remember hearing of a very decisive 

 test of the poisonous quality of that ingre- 

 dient: — a person, intending to build a house 

 on a particular spot, in front of which, how- 

 ever, his neighbour had a row of fine trees, 

 called upon him for permission to remove 

 them, offering him whatever sum of money 

 he would demand for the favour ; this his 

 neighbour positively refused, and was de- 

 termined that the trees should not be re- 

 moved 071 any terms. The person wishing 

 the removal, then told him he must not won- 

 der if God should resent such unneighbourly 

 conduct, adding, " I should not wonder if 

 they do not vegetate the next spring;" and 

 lo, they never did ! not a leaf ever put forth 

 again ! After some years, it was found that 

 holes had been bored in the roots of each, 

 and been filled with the magnesian water 

 from a neighbouring salt work. 



* It is ppcnliiirly the case with the lime used for 

 biiildinf; in Philadelphia ; it will reinnin for mnny 

 days iiiiplaekcd, and is proverbial for its value in build- 

 ing—it contains 41 per cent, of magnesia. 



