TRANSACTIONS OF THE SECTIONS. 37 



produce of the different seasons and plots, are given the propoitiou of corn to 

 straw, and tlie weight per bushel of the corn. 



In the case of the plots without manure, with farm-yard manure, and with 

 ammonia-salts alone, e-^ery year, the ash of the grain of the last sixteen, or more, 

 and of the straw of the last sixteen, of the twenty years, had been analyzed ; and in 

 the case of nine differently manured plots (including the aboYC three), the ash, of 

 both corn and straw, of the ffrst, the last, and two intermediate seasons (one bad 

 and one good) of the last twelve of the twenty years had been analyzed. It was 

 the intention of the authors to publish the results of the investigation in detail 

 before long ; and on the present occasion they confined attention to a few of the 

 most prominent effects of the respective manures on the composition of the crop, 

 when thus applied for so long a continuance, year after j'ear, on the same plot. 



It is first pointed out as remarkable, though fully established by their results 

 from the commencement, that variation in manure, even though maintained for 

 many years in succession, and resulting in great variation in amount of produce, 

 affects' comparatively little either the proportion of corn to straw, or the weight 

 per bushel of the corn ; excepting, indeed, in a few extreme cases of abnormal 

 exhaustion or repletion. Nor do the percentages of dry substance, of mineral 

 matter in dry substance, or of nitrogen in dry substance, vary much under the 

 direct influence of variation in manure, unless again in very abnomial cases. 

 Very different, however, is the effect of season ; the variation in the character of 

 the produce, in every one of the above particulars, being much greater in different 

 seasons with the same manure, than with different manures in the same season. 



Consistently with these broad facts, the composition of the ash of the grain is 

 found to be pretty imiform under a great variety of manuiial conditions in one and 

 the same season ; only in a few extreme cases, of special interest, varying in any 

 material degree. The same may be said in some, though in a much less degree, 

 of the composition of the ash of the straw, which is obviously much more directly 

 affected bj- the character of the supplies within the soil. 



The general result is that (excepting in a few abnormal cases), the variation in 

 the composition of the ash of the grain is limited to the slight variations due to 

 dilfercnces of development] and maturation, which, in their turn, are much 

 greater with variation of season than with variation of manure. The composition 

 of the ash of the straw, on the other hand, much more nearly represents the total 

 mineral matters taken up by the plant, and much less the character of development 

 of its own more fixed and essential constituents. In other words, whilst there 

 may be considerable range in the composition of the matters taken up by the 

 entire plant, the tendency in the formation and ripening of the ultimate product, 

 the seed (whether produced in small quantities or large), is to a fixed and uniform 

 composition, the deviation fi-om which is little directly affected by the character of 

 the supplies -^dthin the soil, but much more by the various inffuences of season. 



The deviations from the point of fixed and uniform composition, thus due pri- 

 marily to variations in climatic circumstance, are, howe^•er, when considered in 

 relation to other characters of the grain, sufficient to show the general connexion 

 between the comparative predominance of individual constituents and that of 

 certain general characters of development. A few illustrations were gi\'en, but the 

 fuUer treatment of the subject, in its bearing on these as well as on other points, 

 was reseiTcd until the results could be considered in the detail necessary to their 

 proper elucidation. 



One point of interest prominently brought out by the results relating to the 

 composition of the straw-ash was, that a high percentage of silica was almost 

 uniformly associated with a bad, and a low percentage with a good condition of 

 the prodtice ; a fact to which the authors had on former occasions called attention, 

 but which, as was remarked by the President, was quite inconsistent with the 

 generally accepted views on the subject. 



Notes of the Analyses of Gold Coins of Columbia, New Granada, Chili, and 

 Bolivia; ivith some account of the operations of Gold Mining in Noicc 

 iScotia. Bi/ Geokge Lawson-, Ph.D., LL.D., Professor of Chemistry, Dal- 

 house College, Halifax, U.S. 



