Page:Journal of botany, British and foreign, Volume 9 (1871).djvu/173

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exercised a generally favourable iiiHuence upon the Grasses up to the time of cutting, but the plants declined in vigour afterwards. In the White Clover and Lotus the development was uniformly high, b it in the T. praiense there was a decline in October.

6. When mineral manures and nitrate of soda were employed together, the effects were generally similar to those in the preceding series (5). This mixture did little to stimulate the growth of one of the plants experi- mented upon, the Plautctf/o lanceolatn, which did not attain muc'i luxuri- ance when dressed with nitrogenous manures.

The above resvdts constitute but a small part of one set of obs nwations in the Report of Drs. Masters and Gilbert. Another set relates to the condition of the plants in the middle of October ; another to the state of the roots of the various plants in the following April (1870) ; while another set gives the contrasts observable between the growth of the root and herbage in the seventy-two experiments. Two admirable features of the Report cannot, however, be left unnoticed, even in the meagr; outline which we have attempted to draw. We refer to the analytical tibles on pp. 6i to 67, and to the diagrammatic i-epresentations of the fluctuations in the growth, etc. of the various plants. These conclude the Report. The analytical work was performed in the Rothamsted Laborat^-y with appliances and with a care which scarcely anywhere else in Englan I could have been obtained. It includes the total weights of dry vegeta')le sub- stance produced in each box, the total weights of the plant as'ies from each experiment, and the percentage proportions of ash to dry v^-getable substance.

AVe quote, as indicating some of the valuable bearings of such inquiries as the present, the concluding paragraph of Dr. Gilbert's remarks : —

" If the results of the first season's experiments do not, as hardly could be expected that they would, afford very satisfactory evidence in regard to the many points of interest which experiments of the kind ar>; calcu- lated to elucidate, at any rate much experience has been gained as to the conduct of future trials; and the discussion of the results themselves can- not fail to indicate how much we may hope to learn when the unfavour- able conditions have been avoided, fiwourable ones carefully secun-d, and the results attentively studied. The relatively varying dependence of different plants on soil and atmospheric conditions respectively, the effects of varying conditions as to soil-supply, the tendency to luxuriance on the one hand or to maturation on the other, or the widely varying special characters of development, according to the external conditions provi(h'd, are points Avhich, when thoroughly investigated and generally understood, must serve to place the cultivation of plants for various purposes — whether for the supply of wood, of fibre, of food, of drug or colour in some special organ, of fruits or of flowers — on the sin-e basis of scientific principle, rather than leave it dependent on the still uncertain, tliouiih often wonderfully successful, guidance of empiricism. May not such knowledge, too, give much insight into the varying functions of plants which have been held to be allied to, or separated from, each other, as- the case may be, for reasons (piite indepeuflent of the sources of their accu- mulation, or the special tendency of their assimilative actions?"

A. II. C.

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