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that each of these globules is furnished with a capsule 
containing the nutritive part — that these globules, 
whether of grain or of roots, are incapable of affording any 
nourishment, as animal food, until they are broken — and 
that a mechanical breaking or grinding is only partially 
efficient, and the only effectual method is by heat or 
panification. Vegetable substances turn the polarized 
ray of light to the right hand in proportion to the 
nutritive matter contained in them. The juice of carrots, 
when boiled, turned the ray at an angle double that of 
raw juice. Similar phenomena were observed in the 
juices of turnips. M. Biot has also determined the 
precise proportion of saccharine matter which the juices 
of the cerealia contain in different stages of their growth, 
and some information is hoped to be gained by his 
experiments respecting the food of plants. 
The rotation of crops upon the whole diluvial beds, 
on both sides of the section, is the Norfolk or four years' 
course. 1 , turnips ; 2, barley ; 3, clover ; 4, maslin. 
But in this course the return of the same crops, and of 
fallow, is too frequent, and red clover is very often a 
failing crop. The following is a remark made upon this 
sort of land in the Quarterly Journal of Agriculture, 
Vol. ix. : "The rotation of four, viz. 1, turnip fallow ^ 
" 2, barley ; 3, grass ; and 4, a white crop, is not 
" adapted to any sand land, even with an unlimited 
" command of manure, for that course keeps light land 
" too much under the plough, makes it too pulverulent, 
"and thereby endangers its texture with deafness. 
" Such land should always be pastured at least two 
" years, and better still for three, in order that it may be 
" consolidated into a firm condition by time, rain, and 
" the tread of animals." A dressing of clay, as tried 
by Mr. Childers, would improve the texture, where 
