12 
The Effect of Climate and Weather on the Soil 
the autumn reserves having been safely locked up m the soil, 
the micro-organic population has become more e cien m 
producing plant food, and the texture of the soil is very 
favourable for the production of a good seed bed. iue 
advantages, therefore, are wholly in favour of a dry, co 
winter, and we can see the wisdom of the old prover s 
“Under water famine, under snow bread.” 
“ A snow year is a rich year.” 
and of the more recent calculation by Dr. W. N. Shaw that 
every inch of rain falling during the autumn months 
September, October, and November lowers the yield ol 
wheat in the next season by a little over two bushels per 
acre from his ideal standard of 46 bushels. 
The older writers, noticing the value of frost and snow, 
thought they had an actual fertilising value, and indeed many 
gardeners and farmers will still contend that snow is a manure 
Opinions of good cultivators are always entitled to respectful 
consideration, and many analyses of snow have been made, 
but they have failed to reveal any appreciable amount ol 
fertilising constituents. Snow differs a little from frost in 
its action ; it forms a non-conducting coat for the soil and 
prevents the temperature from falling as low as it otherwise 
would. How far this affects the soil has not been ascertained, 
no one yet having found out just what degree of cold is 
necessary to bring about these useful results, but any plants 
that happen to be in the soil certainly benefit by the snow 
cover, because their roots are protected from excessive cold. 
A hot dry summer has at least as beneficial an effect on 
the soil as a cold dry winter. The drying out certainly 
changes a heavy soil into clods, but when these are moistened 
again by autumn rains they really fall to a good tilth. If the 
warmth has been sufficient there is an even more marked 
improvement in the soil population as far as food making is 
concerned than after a cold winter, and Mr. and Mrs. Howaid 
have shown that hot weather cultivation in India, which 
facilitates the exposure of the soil to the hot sun, leads to a 
considerable increase in productiveness. In the first y r eai of 
the experiment the increase was six bushels of wheat, in the 
second year it was 12^ bushels. We obtained a similai lesult 
at Rothamsted during'the hot dry summer of 1911 ; some soil 
was exposed in a thin layer to the sun for ten days, and turned 
over at frequent interval's so that every part should be baked 
through and through. It was then transferred to pots and 
sown with buckwheat ; pots of similar soil, which, howevei, 
had not been exposed to the sun, were sown at the same time. 
Other pots were put up of soils artificially dried to 100° F., a 
