GUANO. 



GUANO. 



It has also been analyzed by Mr. Brett of 

 Liverpool, who found in 100 parts 



Parts. 



Earthy insoluble salts, chiefly phosphate of lime 29 4 2 

 Soluble salts, fixed alkaline, sulphate, and mu- 

 riate ------- - - 2-5 



Organic matter - - - - . _ 68'3 



The organic matter consists of 



Lithic acid 16-1 



Ammonia -._____- 87 



Other organic matter and moisture - - - 43-5 



*68-3 



The composition of guano varies, however, 

 considerably. According to the analyses of MM. 

 Voelckel and Klaproth, the varieties which 

 they examined contained 



Voelckel. 



Parts. 



9 



10-6 

 7 

 6 



26 

 5-5 

 33 

 00 

 42 



143 

 4-7 



Klaproth. 

 Parts. 



16 

 00 



1275 

 00 

 00 

 00 



o-o 



05 

 00 

 10 



28-75 



Urate of ammonia - 



Oxalate of ammonia - - - - 



Oxalate of lime - - - - - 



Phosphate of ammonia - 



ammonia, and magnesia 



Sulphate of potass .... 

 soda . . . . 



Chloride of sodium (common salt) 



ammonia - - - - 



Phosphate of lime - 



Clay and sand - 



Undetermined organic substances, of 

 which about 12 per cent, is soluble 

 in water, a small quantity of soluble 

 salt of iron, water - ... 32-53 



In a few words, it may be regarded as a com- 

 pound of urate of ammonia and other salts. 

 There is no doubt but that it is a very power- 

 ful manure ; the very composition of its salts 

 would indicate this fact. Thus, uric or lithic 

 acid, which is a fine white powder, nearly in- 

 soluble in water (1720 parts of water only dis- 

 solving 1 part of uric acid), is composed, ac- 

 cording to Dr. Prout (Thomson's Chem. vol. ii. p. 

 187), of 



Parts. 



Hydrogen - - - - - 0-125 

 Carbon ----- 2250 



Nitrogen or azote 

 Oxygen - - 



5625 



Urate of ammonia and urate of potash are 

 fine white powders, also very insoluble in 

 water: of the phosphate of lime, of the guano, 

 the earthy salt, and most valuable portions of 

 boties, it is unnecessary to comment; I have, 

 in my work "On the Fertilizers, p. 136," en- 

 deavoured to show how essentially valuable 

 this salt is to all the farmer's commonly culti- 

 vated crops. The use of the dung of birds is 

 not a modern improvement, for that of poultry 

 has been adopted as a manure from a very 

 early period. M. P. Cato, the earliest of the 

 agricultural writers, in his work, (lib. Ixxxvi.) 

 commends the use of pigeons' dung for mea- 

 dows, corn-lands, or gardens. And John Wor- 

 lidge, in 1669, was warm in the praise of the 

 dung of fowls. " Pigeons' or hens' dung," he 

 says (Myst. of Jlgr. 71), "is incomparable : one 

 load is worth ten loads of other dung, and is 

 therefore usually sown on wheat or barley that 

 lieth far off and is not easy to be helped." And 

 he says, in another place, " A flock of wild 

 geese had pitched upon a parcel of green 

 wheat, and had eaten it up clean, and sat there- 



* For those I am indebted to Mr. M'Donald, of St. Mil- 

 dred's Court, London, a considerable importer of the 

 guano. 



59G 



on, and dunged it several nights ; that the owner 

 despaired of having any crop that year; but the 

 contrary happened, for he had a far richer 

 stock of wheat there than any of his neighbours 

 had." 



In some experiments made by Mr. Skirving 

 of Walton, near Liverpool, in 1841, the guano 

 was tried at the rate of two or three cwts. per 

 cre, as a manure for Swedish turnips and 

 Italian rye-grass, with very considerable suc- 

 cess; it appeared to be equally, or rather more, 

 efficacious than 20 cubic yards per acre of 

 farm-yard manure. 



The most elaborate set of experiments upon 

 the guano with which I am acquainted were 

 made, in 1810, for potatoes and mangel-wurzel, 

 at the island of St. Helena, by the late General 

 Beatson ; and they are the more valuable from 

 being comparative. The soil on which these 

 experiments were made was rather stiff, being 

 composed of blackish mould, intermixed with 

 friable fat clay. The following table gives the 

 results of every experiment: 35 loads of horse- 

 dung litter per acre were used, 35 of hogs' 

 dung litter, and 35 bushels per acre of the 

 guano. 



1. With potato seed the size of walnuts, 

 planted whole 



Six inches deep. 



Bushels. 

 Guano ------ 554 



Horse dung - .... 583 



Pies' dung ----- 447 



Soil simple ..... 395 



Three inches deep. 



Guano ------ 531 



Horse dung ..... 479 



Pigs' dung - - ... 414 

 oil 



Soil simple 



311 



2. Large potatoes cut in pieces. 



Six inches deep. 



Guano ------ 589 



Horse dung ----- 531 



Pigs' dung 466 



Soil simple - ... 408 



Three inches deep. 



Guano ------ 557 



Horse dung - - - - - 511 



Pigs' dung ----- 375 



Soil simple ..... 414 



3. From middle eye of potato seed scooped 

 out. 



Six inches deep. 



Bushel*. 

 Guano ------ 576 



Horse dung ----- 563 



Pigs' dung ----- 485 



Soil simple 337 



Three inches deep. 



Guano - 

 Horse dung - 

 Pigs' dung 

 Soil simple - 



- 453 



- 343 



4. With small potatoes planted whole. 

 Six inches deep. 



Guano - 

 Horse dung 

 Pigs' dung 

 Soil simple 



583 

 544 

 570 





Three inches deep. 



Guano - 

 Horse dung - 

 Pigs' dung 

 Soil simple - 



- 557 



- 414 



- 440 



- 440 



