58.59 56.14 50.56 66.03 55.16 52.00 67.77 57.90 52.63 67.83 58.70 52.27 66.73 58.77 52.33 66.17 56.27 49.33 67.20 51.90 57.25 59.22 59.72 59.26 The temperature at 2 P. M. is often excessive, and those combinations of soil would seem to be best adapted to vegetable growth which maintain an elevated temperature at other portions of the day, e. g., at 7 A. M., and 9 P. M. Tried by this standard, we find that clay, mixed with 12 per cent. humus, has a temperature higher by 2°.08, than tile clay; and sand, with 12 per cent. humus, has a temperature higher by 20.68 than pure sand, and this relative excess of temperature is maintained through the whole season of active vegetable growth, viz: from 1st of May till 1st of October. It will appear from this, that the farmer has an indirect control over the climate of his fields, through this relation of humus to temperature of soils, when mixed with them. The popular opinion in regard to muck, is expressed in the epithet 'frosty," so generally applied to it. One reason for regarding a mucky soil as predisposed to frost, probably arises from the position it usually occupies, viz: at the bottom of valleys, and other low positions. Into these valleys the air, rendered denser from a loss of temperature, will pour from all the surrouding bigh lands, and hence a lake of cold air will fill each valley, and a slight reduction of temperature by radiation will result in frost, and this frost is the result of position, and does not necessarily arise from the nature of the soil in such valley. Persons who travel in an open carriage at night in summer, and when the air is still, are aware how abrupt is the passage from comparatively warm air on the highlands to the cold air filling a valley, and the equally abrupt change as they rise out of the valley into the warm air covering the opposite bank. All of which is respectfully submitted. LANSING, December, 1868. R. C. KEDZIE. |