280 
On the Failure of Red Clover. 
and thereby endangers its texture with deafness. But there seems 
very little doubt that as both potash and gypsum are necessary con- 
stituents of seeds,* i. e. of cow-grass, white clover, trefoil, and rye-grass, 
of which these seeds, as I am kindly informed by the Duke of Portland, 
consisted, and as neither of them is contained in bones, the boned 
lands failed in consequence of the absence of either the one or the other, 
or perhaps of both of these substances. 
In order, however, that the argument offered concerning the cause 
of failure of the clover after harvest (viz., that it is destroyed by the 
frost, and this in proportion to the want of a certain degree of cohesive- 
ness of the soil) may not lose any of its value by the abstraction of the 
supposed examples of the boned lands, allow me to mention that three 
expedients have been tried in Scotland to remedy the failure of red 
clover : — 
1. Sowing it at longer intervals. 
This plan is said to have succeeded in partially recovering the former 
luxuriance of the crop. However, in Yorkshire, upon the magnesian 
limestone, from inquiries of my own, out of 250 acres which were good 
after harvest, and which were sown at an interval between the same 
crop of not less than twelve years, 14T acres failed. (See Yorksh. 
Agric. Report, p. 123.) 
2. Manuring the land more liberally. 
This to a certain extent has effected an improvement. 
3. The plan which has succeeded most efiectually is, hy alloiving the 
land to remain for a longer period in seeds; and from three to five 
years is now found the proper time. The editor of the Farmer's Ma- 
gazine (p. 170, for March, 1841) says — " However paradoxical it may 
seem to state it as a general principle, that the repetition, or rather 
duration of a crop -which the land is tired of growing, is the best means 
of inducing that land to grow it the more luxuriantly, there is no deny- 
ing the soundness of tiie principle in regard to clover : there is no 
denying that where the experiment of allowing clover to remain a 
number of years, that is, white clover (for red clover is only available 
for one year) to be dcjiastured by stock, has been tried, tiiere the growth 
of red clover has become almost certain." 
My theory explains this seeming paradox ; for the longer any land 
is kept from the action of the plough, and the more it is trodden by 
sheep, the firmer does it become ; the particles, particularly the silicious, 
luiite more firmly by the force of homogeneous cohesion, and the soil is 
reconsolidated ; and hence, for reasons before mentioned, the clover is 
not affected by the frost. 
I wish also, in corroboration of the truth of the theory, to name the 
practice of a magnesian-limcstone farmer, who has upon the same land 
grown red clover every fourth year for thirty years, while the owners of 
the adjoining fields cannot produce it even every twelfth year, with the 
same certainty that it will endure the winter. 1. He gives the clover 
ley, when broken up for wheat, a good dressing of caustic lime, which not 
only rots out much sooner the vegetable matter, but also gives a certain 
* See Lectures on Agric. Chemistiy, by Prof. Johnstone, No. xv. p. 323. 
