On the SohUion of Bones in Snlphnric Acid. 400 
nurlnj^ substance. This being phosphate of lime, chemistry sug- 
gcsted that since the lime was in so small a quantity, the phos- 
phoric acid united with it must be the true manure contained in 
the bones, and that if ihe lime were taken from it by sulphuric 
acid, the phosphoric acid thus set free would be greatly strength- 
ened in its immediate activity. This the Morayshire farmers 
carried last year into effect, and the Duke of Richmond in the 
present year, the result wonderfully according with the predictions 
of chemical science. We cannot even now regard this discovery 
as completely established; but as it promises a very great saving 
to farmers who buy bones largely, I hope that the hint will be 
followed up until certainty has been attained. Hitherto the dis- 
solved bone, or gruel, as one farmer calls it, has been mixed with 
large quantities of water, and applied as a liquid manure ; 
but the use of any liquid manure is so laborious and inconve- 
nient, that I should greatly prefer, as a trial at least, to mix the 
dissolved bones with some dry earth or ashes, which might be 
used by the ordinary method of drilling. Pu. Pusey. 
XXX. — Statement of a new and successful Rotation of Crops fur 
Heavy Clays. By J. S. Nowlson. 
To Ph. Pusey, Esq. 
Sir, — INIy course of crops is as follows, viz. one-fourth wheat ; 
after that oats,* one-half of which is sown alternately with 
* As a general rule applicable to much, perhaps most, of the soils of this 
country, the alternation of corn and green crops is better than two corn 
and two fallow crops in succession ; but on land of the peculiar character 
of that in Northaw it is otherwise, and a comparison of Mr. Nowlson's 
crops with those grown on similar land in the neighbourhood, managed on 
the alternate system, sufficiently proves that that rule must not be taken 
to be without exceptions. 
Nyn Farm is situated at the northern extremity of the extensive parish 
of Northaw, which is a border parish of the county of Herts. On the south 
is that wild part of Middlesex once Enfield Chase, but now enclosed and 
cultivated. Tlie quality of the land in Northaw varies considerably, but its 
general character is that of a wet and singularly tenacious clay (on the 
plastic clay formation), interspersed in places with beds of rounded gravel.- 
These beds are merely superiicial — that is, few of them are more than 6 
feet deep, and they have invariably the stiff clay beneath them. Chalk 
can in many places be reached, on Nyn Farm, at the depth of GO feet ; 
and about thirty years ago, when great part of the farm was enclosed from a 
state of common by Thompson of Northaw (a name well known to the 
readers of Cobbett), much chalk was raised, and used in bringing the land 
into cultivation, the good effects of which are visible to this day. The 
arable land has been completely drained with bushes, as is common in 
this district ; and the drains having been laid at 18 feet apart, the land 
