A FIRST REPORT ON THE RELATIONS BETWEEN 
CLIMATES AND CROPS. 
PART I.—LABORATORY WORK, PHYSIOLOGICAL AND EXPERI- 
MENTAL. 
Chapter I. 
GENERAL REMARKS. 
It is not possible to conceive of an intelligent solution of the com- 
plex problems offered by plant life in the open air and cultivated 
fields without first considering the innumerable experiments that 
have been made by experimental botanists. It is therefore necessary 
for the student and the practical man alike to know something of the 
laws of growth, as presented in the elaborate treatises by Sachs, Vines, 
Goodale, and others. I will at present simply collate those special 
results that bear upon crops as the final object of agriculture and 
confine myself very closely to the relation between the crop and the 
climate, in order to avoid being drawn into the discussion of innumer- 
able interesting matters which, although they may affect the crop, 
yet are understood to be outside the province of climatology. By 
this latter term I understand essentially the influence on the plant of 
its inclosure, i. e., the sky or sunshine, soil, temperature, rainfall, and 
the chemical constitution of the air, either directly or through the 
soil. 
THE VITAL PRINCIPLE—CELLULAR AND CHEMICAL STRUCTURE. 
The growth of a plant and the ripening of the fruit is accomplished 
by a series of molecular changes, in which the atmosphere, the. water, 
and the soil, but especially the sun, play important parts. In this 
process a vital principle is figuratively said to exist within the seed or 
plant and to guide the action of the energy from the sun, coercing 
the atoms of the soil, the water, and the air into such new chemical 
combinations as will build up the leaf, the woody fiber, the starch, 
the pollen, the flower, the fruit and the seed. 
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