84 Salt, as a Manure. 



general are lighter, in proportion as the quantity of salt is 

 large, which leads directly to the conclusion, that salt is inju- 

 rious to vegetation, and it certainly is so when too fi'eely 

 applied, but, in small quantities, I think it useful. The way in 

 which I think it most calculated to do good is, when mixed 

 up with the dunghill in trenching, in about the proportion of 

 from twenty to twenty-eight parts of salt to a cubic yard of the 

 untrenched dunghill, and although it may not increase the 

 apparent bulk of the crop, it will improve the quality. The 

 barley, manured with salt, appeared to me to be heavier in 

 the grain, in proportion as the quantity of salt was large ; 

 and I found, by selecting at random from the barley grown 

 with salt at the rate of 2 tons to an acre, 



r 103 grains, grown on salt, at IJ ton per acre. 

 . I 106 grains, grown on salt, at 1 ton per acre. 

 00 grains j, ^^g grains, grown no salt, at a a ton per acre, 

 weigft exactly | ^^^ ^j^^.^^ grown on pigeon dung; and 



1, 1 10 ditto, grown on common compost dung. 



I am not chemist enough to analyse my barley, and recover 

 from it the salt taken up in its growth, nor will I enter into 

 any argument with your more learned correspondents, as to 

 whether salt is the food of plants, or only a stimulus ; I merely 

 state the results of a few simple experiments, minutely made, 

 and easily understood. I hold a medium belief between the 

 opinion of those who say salt is of no use, and of those who 

 affirm it to be the ne plus ultra of manures. Salt, mixed with 

 our food, is agreeable, and, I dare say, useful to the con- 

 sumer, but it does not follow that any man would be long 

 preserved in health without other sort of aliment. 



Last summer I had collected a large heap of couch, and 

 other weeds, from the ground on which a crop of turnip seeds 

 had been grown, and the weather being showery, it grew into 

 one mass of roots, with a crop of grass on the suriace that 

 might have been made into hay. I applied over the whole 

 of the heap a thick covering of salt, and, in less than a week, 

 not a vestige of vegetation was to be seen, and when turned 

 over soon after, and a new surface exposed, no second growth 

 appeared ; it is now a mass of rich mould, and I purpose 

 mixing it up with dung. Should you think these remarks 

 worth insertion in your very useful Magazine, they are very 

 much at your service, and I am in the meantime, with sincere 

 respect, 



Sir, your most obedient servant, 



Robert Forbes. 

 Pinefield Nurseries, near Elgin, Jan. 1828. 



