GUANO.
139
the borax water. These 33-8 consisted of subphospliate of lime 17, magnesian phos-phate of ammonia 5-5, silica 0-7, and combustible organic matter 10-6.
The ammonia in the soluble portion was in the state chiefly of phosphate; there wasMerely a faint trace of oxalate of ammonia.
E. African Guano. —Among the many samples of African guano which I have hadoccasion to analyze for the importers, none has contained any appreciable quantity°f uric acid, or by consequence of potential ammonia. The best afforded me 10 percent. of ready-formed ammonia, existing chiefly in the state pf a phosphate, though theyail contain carbonate of ammonia, and have of consequence an alkaline reaction. Thes uid sample contained 2T5 of moisture, separable by a heat of 212° F. Its specificGravity was so low as T57, in consequence of the large proportion of moisture in it.it contained 23 per cent, of subphosphate of lime, 3 of magnesian phosphate of am-£Q onia, 1 of silica, and T5 of alkaline sulphate and muriate. The remaining 50 partsinsisted of decayed organic matter, with phosphate of ammonia, and a little carbonate,et luivalent to half a grain of ammonia, which is the largest quantity in such guanos.Other African guanos have afforded from 24 to 36 of moisture, no uric acid; no po-tential ammonia; but decayed organic matter; from 5 to 7 of ready-formed ammonia in9'e state of phosphate, with a little carbonate; from 25 to 35 per cent, of subphosphate°f lime; 5 or 6 of the magnesian phosphate of ammonia; more or less oxalates fromthe decomposition of the uric acid, and 3 to 5 per cent, of fixed alkaline salts.
F. The Chilian Guano gathered on the coast, already adverted to, contained a remarka-ble proportion of common salt, derived probably from the sea spray.
The following is the general report of the chemical examination of severalRumples of guano, which I made for Messrs. Gibbs of London , and Messrs. Myers ofLiverpool:—
“ In these various analyses, performed with the greatest care, and with the aid of the°|ost complete apparatus for both inorganic and organic analysis, my attention has beenErected, not only to the constituents of the guano which act as an immediate manure,but to those which are admitted by practical farmers to impart durable fertility to thegrounds. ■ The admirable researches of Professor Liebig have demonstrated that Azote ,the indispensable element of the nourishment of plants, and especially of wheat andot hers abounding in gluten (an azotized product), must be presented to them in the state°f ammonia, yet not altogether ammonia in the pure or saline form, for, as such, it istoo readily evaporated or washed away; but in the dormant, or as one may say, in thePotential condition in contradistinction from the actual. Genuine Peruvian and BolivianSuanos, like those which I have minutely analyzed, surpass very far all other species°f manure, whether natural or artificial, in the quantity of potential ammonia, and,therefore, in the permanency of their action upon the roots of plants, while, in conse-lUence of the ample store of actual ammonia which they contain ready formed, theyar e qualified to give immediate vigor to vegetation. Urate of airmonia constitutes ac °Usiderable portion of the azotized organic matter in well-preserved guano; it ishearly insoluble in water, not at all volatile, and is capable of yielding to the soil, bylts slow decomposition, nearly one third of its weight of ammonia. ]\ T o other manureCy h rival this animal saline compound. One of the said samples tf guano afforded men ° less than 17 per cent, of potential ammonia, besides 4h per cent, of the actual orr eady formed; others from 7 to 8 per cent, of ammonia in each of these states re-spectively. These guanos which I have examined are the mere excrement of birds,^nd are q U it e f re e from the sand, earth, clay, and common salt, reported ih the analyses?* some guanos, and one of which (sand) to the amount of 30 per cent. I found myselfIri & sample of guano from Chile .
y <c The Peruvian guano, moreover, contains from 10 to 25 per cent, of phosphate ofthe same substance as bone-earth, but elaborated by the birds into a pulpy con-sistence, which, while it continues insoluble in water, has been thereby rendered more£ e &dily absorbable and digestible (so to speak) by the roots of \ lants. I have there-t ° r . e no doubt, that by the judicious application of these genuine guanos, mixed with^ice or thrice their weight of a marly or calcareous soil, to convert their phosphate oftlJ hionia into phosphate of lime and carbonate of ammonia, as also to dilute all theirjhhtnoniacal compounds—such crops will be produced, even un sterile lands, as thehrtner has never raised upon the most improved soil by the best ordinary manure. ^ Tohe‘VVest India planter, guano will prove the greatest boon, sirce it condenses in aPortable and inoffensive shape the means of restoring fertility to his*exliausted cane-a benefit it lias long conferred on the poorest districts of Peru ,i. I respectfully observe, that no analysis of guano hitherto n ade public at all ex-erts the value of the cargoes referred to above, while none gives the quantity ofJjhimonia dormant in the azotized animal matter of the birds' dung, which, called intogotivity with the seeds in the soil, becomes the most valuable of its constituents, as a°hrce of perennial fertility. In the detailed account of my am lyses of this complex