544 



Si'cicty, will repay all who are interested in agricultural 

 progress. We confine our attention now to one of the 

 series— viz., the result of growing wheat for twenty 

 years in succession on the same piece of ground, with- 

 out manure of any description. The land was pre- 

 viously reduced to its natural state by a course of 

 cropping. We should have supposed that after bear- 

 in"- three or four crops the land would have become 

 so completely exhausted that it would cease to pro- 

 duce. Not so, however ; on the contrary, the produce 

 was as good at the end as at first, the average being 

 i6. 1 bushels per acre; the maximum 17. 1 bushels; 

 the minimum 5^4 bushels, according to seasons. A 

 most important fact is thus established— viz. , that soils 

 possess a natural production on which we can depend. 

 It is in order to increase this natural yield to its utmost 

 limit that we introduce rotation crops, expend large 

 sums in feeding materials, and scour the earth for 

 sources of extraneous manures. 



OFFICE OF ARTIFICIAL MANURES. 



The development of the artificial manure trade has 

 been most remarkable ; and, whilst unmistakably 

 advantageous from one point of view, we are led to 

 question whether the facility with which we have 

 been supplied has not led us to be careless about our 

 own resources. The very materials for which we 

 pay so heavily are too often permitted to ooze away 

 into the nearest ditch and pollute our streams. Baron 

 Liebig, to whose investigations we owe in a great 

 degree our present knowledge, denounces this terrible 

 waste, and warns us that the time will come when 

 our reckless extravagance will bring down on us heavy 

 discomfort; and that the decay of our great country 

 will date from the day when our supplies of phos- 

 phates fall short. Without going quite so far, we 

 would earnestly impress our readers with the impor- 

 tance of taking care of the manure of the farm. It 

 is sad to see the ignorance that is apparent in un- 

 spouted yards, washed-out manures, and the porter- 

 coloured horsepond. Even if it could be proved that 

 the waste thus incurred can be more economically 

 made up by the purchase of artificials than by the 

 outlay necessary to prevent it, it would still be 

 clear that, taking a comprehensive view, and duly 

 considering the future, our practice is most reprehen- 

 sible. 



The proper office of artificial manure is as an auxi- 

 liary, only to make up the deficiency which a forcing 

 system requires when every care has been bestowed 

 upon the home supply ; and it should ever be remem- 

 bered that it is more profitable to enrich our land 

 through the animal's body than to depend upon arti- 

 ficial manures. " The sheep's belly is the best ditro. 

 cart.'' The increase of flesh resulting from the use 

 of purchased food will often cover the outlay, whilst 

 the improvement of the manure is equal to from one- 

 fourth to one-half of the cost. The statistics of the 



T/ie Country Gentleman s Magazine 



manure trade are remarkable. In 1S41 and 1842 Mr 

 Lawes, acting upon the suggestions of Liebig, com- 

 menced the manufacture of superphosphate of lime. 

 At first bones only were employed as the source of 

 the phosphate ; now phosphatic materials of mineral 

 origin, such as apatite and coprolites, and inferior 

 guanos from which the ammoniacal matters have 

 been dissipated by time or moisture, or largely em- 

 ployed ; and we are within bounds in estimating 

 the present consumption at over 250,000 tons per 

 annum. 



Peruvian guano, as a trade, was established in 1842. 

 At first the demand was very limited. Thus Messrs 

 (iibbs imported in 1842 only 182 tons, whereas 

 twenty years after — viz., in 1862, 435,000 tons reached 

 our shores, of which from one-third to one-fourth was 

 used in the United Kingdom. The price at first 

 ranged from ,^lO to £1^ ; from 1846 to 1848 it sunk 

 to £() ; rose to ;i^lO in 1854 ; ;^II in 1855 ; £12 in 

 1856 ; and £12, in 1857. At the present time the 

 price is ahoni £i2i a ton. Artificial manures may be 

 separated into two groups ; those that, like guano 

 and certain composite productions, supply the various 

 minerals and ammonia required for the additional 

 produce beyond that which the soil can afford ; and 

 simple substances like nitrate of soda, sulphate of 

 ammonia, salt, and, to a certain extent, superphos- 

 phate of lime. These latter supply one or at most 

 two important materials of plant food, and their action 

 is not so much as direct manures, but as stimulants, 

 which enable the plants to absorb more the soil ; 

 just as we give a tonic in order that the animal's 

 system may digest more food. This is an im- 

 portant distinction, which should be borne in mind 

 and materially nfluence our views as to tenant right 

 for unexhausted manures. We give one illustra- 

 tion. 



Nitrate of soda as a top-dressing for wheat su]>plies 

 an amount of nitrogen less than is contained in the 

 extra produce which it induces ; hence the additional 

 nitrogen and all the minerals must have been obtained 

 at the expense of the soil. Such a manure is there- 

 fore more or less exhausting, and its use will depend 

 upon the supply of mineral food in the soil. We have 

 known compensation given to tenants for all the nitrate 

 of soda used on the last crop, whereas in reality the 

 outgoing tenant should be taxed for exhausting 

 the soil. 



PERUVIAN GUANO. 

 Peruvian guano heads the list of extraneous 

 manures ; long may it occupy that position. Its 

 value depends upon its completeness, and especi- 

 ally upon the large proportion of nitrogen, which, in 

 the form of ammonia, should average from 17 to 19 

 per cent. Of this 6 to 7 per cent, exists as ready-made 

 ammonia, and the remainder is made up of various 

 nitrogenous combinations, which on decomposition 

 yield from lo to 12 per cent, of ammonia. The phos- 



