242 On the ]\Iamirii:g of Grass Land. 



" The next experiment I tried, and the Inst tlrat I shall mention on this 

 occasion, was one to ascertain whether the aflinity of the soil for salts of am- 

 monia extended to other salts. Ten grains of common salt were mixed ^ith a 

 portion of the soil last mentioned, and water poured upon it till 12 oz. had 

 passed through : on evaporation [of the water which had filtered through the 

 soil], 9 grains of the salt were indicated by its equivalent of chloride of silver 

 being obtained. iS'ine-tenths of the salt applied were thus washed out un- 

 changed by the first 12 oz. of water which j assed through the soil ; and the 

 inference is clear that, if the application of common salt be of any service to 

 light land, the benefit can only be of a very temporary nature." 



Supposinj^ this to apply generalh', it indicates a necessity for 

 small annual dressings of salt for the hay-crop, instead of a heavy 

 dressing once in a series of years, and, since it is the body in 

 minimo which rules the crop, establishes a probability that the 

 hay-crop is often less than it would be owing to the want of com- 

 mon salt. 



The following instance may show the effect oi jmrtial instead 

 of complete manures : — ■ 



Bones. — Bones are said to produce wondrous results upon the 

 old grass-land of Cheshire, as tlieory would lead us to expect. 

 Dairy pasture is continually robbed of phosphates to supply the 

 recjuisite quantity for the daily yield of milk, whereas, if those 

 pastures were stocked with fattening cattle, nearl}^ all the phos- 

 phorus would be returned in the excreta. We are cjuite prepared, 

 theiefore, to find that a large dressing of bones produces large 

 and lasting influence upon the Clieshire dairy land. Still we 

 shall err greatly if we consider bones an adequate manure for 

 grass. They can only act by supplying a j)art of the wants of 

 A'egetation, and, in whatever excess they may he applied, will fail 

 to produce an effect, unless all the other food required for growth 

 be available. This w'as well exemplified by a case which came 

 under my notice. A gentleman of my acquaintance had heard 

 of bones for gi-ass, and determined to try them. He applied a 

 ton per acre of ground bones to a field near his house, and had, 

 to use his own expression, a forest of grass, lie never saw so 

 large a crop. It was generally estimated at three tons of hay per 

 acre. The after-grass was also an enormous crop, nearly equal to 

 the first. Being ignorant of chemistry, and thinking that land 

 could not have too much of a good thing, he gave the same field 

 the same quantity of the same kind of bones the following year, 

 when he expected a result similar to that obtained before. This 

 time, however, he was disappointed ; for, n(jt\vitlistanding his ton 

 of bones per acre, containing, besides phosphates, much gelatine, 

 with 18 or 19 per cent, of nitrogen, he had not ai)ove an ordinary 

 crop. He and his neighbours were utterly puzzled. It was clear 

 that the bones brought the crop before, and therefore, in their 



