ness of the material is such as to involve its being first ground and then treated with oil of vitriol to turn it into a superphosphate before it can become available as manure. With the highly phos- phatie yet powdery and soft guanos of Peru and Bolivia such treat- ment is rarely necessary, but it is essential with Navassa (Caribbean Sea) and with the Sombrero Island (Gulf of Mexico) guanos. The latter variety contains no nitrogen, and is very hard, but contains on an average no less than 75 per cent. of tricalcic phosphate. It has been said that the imports into Great Britain of this Sombrero phosphate have been so large that the whole island has been trans- ported thither.
Some notion of the main constituents of Peruvian and Bolivian gnanos may be gathered from the following figures, which roughly represent the nature and percentage proportions of the chief con- stituents of fair samples from several localities:—
| A table should appear at this position in the text. See Help:Table for formatting instructions. |
e | 2 |22\ 24] 2 & | & |27)e3| 2 24/5 [€s|£4] 2 Moisture. 2.0... cece cece eee cee eee eee eens 11 | 16; 17/16 | 13 Organie matter and combined water ....[53 | 52 | 45 |34 | 23 Whereof is nitrogen equal to ammoniaj 17-5] 17 | 12 | 7-5) 4 Tricalcic phosphate.............0eeeee ee 19 | 22 | 19 |29 | 42 Phosphorus pentoxide in alkaline salts | 1 3] 4] 3 3 Alkalies, &e., by difference................. 9 6 | 12 ])13 | 12
One specimen of Angamos guano actually contained 25 per cent. potential ammonia and but 6 per cent. phosphates reckoned as tricalcic phosphate. It will indeed be seen how generally with the diminution of the nitrogenous organic matter the phosphates in- crease, and vice versa. Analyses of guanos from many different countries exhibit the same feature. But even the phosphatic guanos are less rich in phosphates than one might expect, owing to the intrusion of siliceous matter. In some guanos analysed by Nesbit more than 30 per cent. of sand occurred. Californian guanos gave this analyst from 14 to 84 per cent. ammonia, and about 30 per cent. phosphates. In Falkland Island guano he found about 3 to 23 per cent. ammonia and 20 to 25 per cent. phosphates. In the case of so variable a material as guano neither analyses of indi- vidual specimens nor averages can be considered as really repre- sentative. But it is instruetive to note how low a proportion of nitrogen is present in many of the guanos from different countries:— Algoa Bay, °5 per cent. of potential ammonia; Ascension Island, 6°0; Queensland, 1°0 ; Chili, 1°4; Ecuador, °8; Mexico, -4; Pata- gonia, 2°7; Tasmania, 2°5.
In the guanos imported during 1847-48 Mr J. T. Way found the following average percentages of ammonia (calculated from total nitrogen) and of phosphates (calculated as tricalcie phosphate) :—
| A table should appear at this position in the text. See Help:Table for formatting instructions. |
Ammonia. Phosphates. Peru (13 samples)................ 17°41 24°12 Ichaboe CLL gg ease eaceeeen ees 7°30 30°30 Patagonia (14 gg a cee eec eee ee ees 2°54 44°60 Saldanha Bay (20), 0). cee sees eee ees 1°62 56°40
Dr Voelckcr’s analyses of samples taken in 1874 from the undermentioned places gave about 25 per cent. phosphates, and of ammonia 8 to 12 per cent. in guanos from Pabellon de Pica, 3 to 12 per cent. from Lobos, and 8 to 124 per cent. from Huanillos.
The Lobos guanos, having since then become of generally inferior quality, have been but sparingly imported during the last few years. The percentage of ammonia in recent cargoes of guano from Punta de Lobos has been 5 to 6, from Huanillos 9, and from Pabellon de Pica 11 to 12.
The analysis of guano for commercial purposes is generally limited to the quantitative determination of three constituents, — the nitrogen, the soluble phosphorus pentoxide, and the insoluble phosphates ; the latter are usually reckoned as tricalcic phosphate. The processes of analysis require a few special precautions. One of these consists in mixing the guano in the combustion tube itself when making a nitrogen determination by Will and Varrentrapp’s method ; otherwise a loss of ammonia may occur.
Asa manure the nitrogenous guano of Peru is rich, active, and stimulating. It has a decided tendency to cause an excessive development of foliage, and is therefore peculiarly fitted for appli- cation to grass and to other plants the devclopment of the stem and Teaf of which is desired. Its effects on clover are less marked. Mixed with superphosphate it may be applied to potatoes or root-crops, and to most of the plants of the kitchen garden ; for many plants cultivated for their flowers it may be used also, but with great care and moderation, mixed with water or dry soil. On light and cal- carcous lands sown with swedes, turnips, or mangolds, guano has frequently been found to burn and destroy the young plants or even to prevent the germination of the seed ; ‘dissolved ” guano is less liable to eause this injury.
Guano, with another very useful natural product, namely, nitrate of soda, constitutes the chief source of revenue for Peru.
The following papers and reports in the Journal of the Royal Agricultural Society contain interesting information on guano, ser. i. vols. ii. p. 301; x. p. 196; xxv. p. 186; ser. ii. vols. 1. p. 213; v. 92; vi. 142, 403 ; vii. 367 ; viii. 220; ix. 261; x. 541. Native guano is discussed, ser. ii. vol. vi. p. 415. The Jahresbericht der Agricultur-Chemie contains a digest of most of the important papers on guano published on the Continent; see, ¢. g., 1858-9, pp. 231-238; 1860-1, pp. 186-191; 1862-3, pp. 150-157 ; 1867, p. 189; 1870-2, pp. 190-195 ; 1873-4, iii. pp. 10-26. A pamphlet published in 1874 by Dunlop & Co., London, gives some important statistics and reports on the Peruvian guano then remaining ; as also does the Commercial Blue Book, No. 23, 1878, pp. 525 to 539.
GUARANA, so called from the Guaranis, an aboriginal American tribe, the plant Paullinia sorbilis, Mart., of the natural order Sepindacece and tribe Sapinde, indigenous to the north and west of Brazil. It has a smooth erect stem ; large pinnate alternate leaves, composed of 5 oblong-oval leaflets ; inflorescence in narrow panicles of short-stalked flowers, having 4 or 5 sepals and 4 petals, 8 stamens, and a cylindrical 3-celled ovary; and fruit ovoid or pyriform, about as large as a grape, and containing usually one seed only, which is shaped like a minute horse-chestnut. What is commonly known as guarana, guarana bread, or Brazilian cocoa, is prepared from the seeds as follows. In October and November, at which time they become ripe, the seeds are removed from their capsules, and sun-dried, so as to admit of the ready removal by hand of the white aril; they are next ground in a stone mortar or deep dish of hard sandstone ; the powder, moistened by the addition of a small quantity of water, or by exposure to the dews, is then made into a paste with a certain proportion of whole or broken seeds, and worked up sometimes into balls, but usually into rolls not unlike German sausages, 5 to 8 inches in length, and 12 to 16 oz. in weight. After drying by artificial or solar heat, the guarana is packed between broad leaves in sacks or baskets, Thus prepared, it is of extreme hardness, and has a brown hue, a bitter astringent taste, and an odour faintly resembling that of roasted coffee. An inferior kind, softer and of a lighter colour, is manufactured by admixture of cocoa or cassava. Rasped or grated into sugar and water, guarana forms a beverage largely consumed in 8. America. Its manufacture, originally confined to the Mauhés Indians, has spread into various parts of Brazil.
The properties of guarana as a nervous stimulant and restorative are due to the presence of what was described as a new principle, and termed guaranine, by Dr T. Martius, but which was proved by Berthemot and Deschastelus (Journ. de Pharm., vol. xxvi., 1840, p. 518 sq.) to be identieal with caffeine or theine, CgHyyN4Og +H,0. Of his alkaloid guarana yields 5°07 per cent., against 2°13 in good black tea, ‘8 to 1 in coffee beans, and 1°2 in miaté or Paraguay tea (Stenhouse, Pharm. Journ., xvi. p. 218); for medical purposes it may in fact be regarded as “ practically a convenient form of impure caffeine” (F. E. Anstic, Braithw. Retrosp., 1878, i. p. 35). Besides this substance, which is stated to exist in it in the form of tannate, guarana yields on analysis the glucoside <:ponin, with tannin, starch, gum, three volatile oils, and an acrid green fixed oil (Fournier, Journ. de Pharm., vol. xxxix., 1861, p. 291). As a medicine, guarana was first described in 1817 by Cadet de Gassicourt, to whom a specimen was sent from Brazil (see Bud. Gen. de Thérap., lii., 1857, p. 497 sq.), in which country it is in popular repute as a stomachic, febrifuge, and aphrodisiac, and more especially as a specific for dysentery and diarrhcea, in which latter disease it is given in very large doses—4 to 8 or 19 grammes (Bull. Gén, de Thérap., liti. p. 139). It is said by Martius (Syst. dat. Med. Veget. Brasiliensis, p. 59, Leipsic, 1848) to diminish fever by its tonic effects on the nerves, to invigorate the stomach and intes- tines, to restrain excessive mucous discharges, to increase the action of the arteries and heart, and to promote diaphoresis. In migraine, or sick-headache, it has oftentimes been found a most serviccable remedy (see inter alia, Brit. Med. Journ., 1872, i. pp. 421 wand 426 ; Practitioner, Aug. and Sept. 1873, pp. 100-102, 161-175) ; and it has been recommended in lumbago when the pain is of a stinging nature (Rawson, Braithw. Retrosp., 1874, ii. p. 33), and in sciatica and blennorrheea.
See Spix and Martius, Reise in Brasilien, vol. iii. pp. 1061 and 1098, Munich, 1831; Hooker’s Journ. of Botany, vol. iti., 1851, pp. 1938-4; Bentley and Trimen, Medicinal Plants, pt. 4, tab. 67, 1876; and, on the preparation of ‘‘ Guaranine,” Journ. de Pharm., 4th ser., xviii. p. 224. On the ‘‘ Antagonism between Guaranine
