THE FARMER'S MAGAZINE. 



S79 



branch of agriculture. The use of oil cakes had 

 become more extended : crushed bones had been 

 introduced. But another ten years elapsed before, 

 in 1839, a few barrels of Peruvian guano were first 

 imported into England, and (what may be regarded 

 as the first dawn of the manufacture of artificial 

 manures) the use of superphosphate of lime was 

 in the same year suggested by Professor Liebig. 



From such a rather recent period we may date 

 the establishment of those great manufactories 

 where the most powerful manures are now so skil- 

 fully and so largely prepared. It was about the 

 year 1S40-41, that the first of these, the works of 

 Mr. T. B. Lawes, and of tlie London Manure 

 Company, were erected — manufactories which have 

 since been imitated by other manufacturers in most 

 portions of the United Kingdom. Of the extent 

 to which artificial manures are now employed. 

 Professor Anderson has recently made some ap- 

 proximate estimates (T/-«//5.H/^A. 5'oc.,1860,p.430), 

 combining with these a variety of very valuable 

 suggestions, as to the valuation and the reading of 

 the analyses with which the dealers may furnish 

 the farmer. This estimate is attended with many 

 sources of error ; and as Dr. Anderson observes ; — 

 "Where the substances are of foreign origin, 

 and used exclusively for agricultural purposes, no 

 difficulties are experienced ; and we thus learn, 

 from the Board of Trade returns, that the value of 

 the guano imported into this country in the 

 year 1S58, and retained for home consumption, 

 amounted to no less than £3,857,424. This sum, 

 however, is considerably above the average, but it 

 is probable that the usual import is not less than 

 £2,500,000. 



" Next to guano the largest consumption is that 

 of bones, of which, including bone ash, 84,000 

 tons are imported annually. In addition to this, 

 however, it is necessary to take into account the 

 bones collected in this country, of which it is only 

 possible to form an approximate estimate. In 

 Glasgow, there are collected about 6 tons 2 cwt. of 

 bones for every 1,000 of the population, and if this 

 were the case all over the kingdom, the quantity 

 would amount to upwards of 150,000 tons; but in 

 country districts a considerable quantity of bones 

 are lost, and the consumption of meat is also much 

 smaller than in towns, and I do not think the quan- 

 tity of bones collected can be safely estimated at 

 more than 50,000 tons — giving, for the total quan- 

 tity of bones used, 134,000 tons." (If we take the 

 population of our island to be 24,000,000, the aver- 

 age consumption of meat by each individual 75ll)s., 

 and that this weight contains 12 lbs. of bones, that 

 would give an annual yield of bones equal to 

 128,571 tons). "Avery large proportion of the 

 bones collected in this country is converted into 

 animal charcoal for the sugar refiners, but as the 

 spent charcoal eventually finds its way into the 

 hands of the manure manufacturer, it is not neces- 

 sary to take this into consideration ; but I estimate 

 the quantity used in the manufacture of ivory black, 

 for turning, &c , at 20,000 tons, leaving 114,000 to 

 be employed in agriculture. Of this probably 

 40,000 tons are to be used as bone dust, costing 

 the farmer £6 per ton, which is equal to £240,000, 

 and 74,000 are converted, by the action of acid. 



into 110,000 tons of superphosphate, which, at £7 

 per ton, is worth £770,000. 



" The consumption of mineral phosphates, as far 

 as I have been able to ascertain, is as follows :— 



Tons. 



Cambridge coprolites 40,000 



Suffolk coprolites 3,000 



Apatite, and all other mineral phos- 

 phates 5.000 



48,000 



which, being entirely converted into super- 

 phosphates, will yield 72,000 tons, at £5, value 

 £360,000. 



" Of nitrate of soda the average imports amount 

 to 26,000 tons, of which about one-half— worth, 

 at £15 per ton, £195,000— is used for agricultural 

 purposes. 



" Of sulphate of ammonia it is difficult to obtain 

 any definite information, but the opinion of persons 

 conversant with the manufacture is, that about 

 6,000 tons are used as manure, which, at £15 per 

 ton, is worth £90,000. 



" If we add to this the sum of £50,000, as cover- 

 ing the value of the blood, fish-oftal, animal matters 

 of all kinds, potash, salts, &c., &c., used in the 

 manufacture of manures, we have the following 

 general statement : — 



Guano £2,500,000 



Bone dust, 40,000 tons, at £6 . . 240,000 



Superphosphates, made from 

 bones and bone ash, 110,000 

 tons, at £7 770,000 



Superphosphate from coprolites, 



72,000 tons, at £5 360,000 



Nitrate of soda, 13,000 tons, at 



£15 195,000 



Sulphate of ammonia, 6,000 tons, 



at £15 .. » 90,000 



All other substances — say . , . . 50,000 



£4,205,000" 



Let us compare this enormous estimated amount 

 of artificial dressings with that of our ordinary 

 farm-yard dung; and here, again, let me quote 

 Professor Anderson. He adds : — 



" It would be very interesting, were it possible, 

 to ascertain what relation this large sum bears to 

 the value of the farm -yard manure annually con- 

 sumed throughout the country ; but on this point 

 it is not easy to obtain any rehable information. A 

 vague estimate may perhaps be obtained from the 

 number of acres of land under cultivation. It is 

 said that the land under tillage on the British 

 Islands exceeds 24,000,000 acres, and though this 

 is probably above the mark, it may be adopted 

 without much error. If it be assumed that one- 

 fourth of this is annually manured to the extent of 

 ten tons Tier acre with farm-yard manure, the 

 annual consumption must be 60,000,000 tons, 

 worth about £20,000,000. It is probable that this 

 estimate is too high, but it shows that at least one- 

 fifth of all the manures now used is artificial, and 

 chiefly derived from foreign sources." 



The average value of the farm manure assigned 

 »* B* 2 



