PHOSPHATES. 



PINE TREE. 



third specimen, from a naturally barren soil, he 

 could not detect any phosphoric acid. 



Under the heads of BONES and ACIDS, will be 

 found much valuable information relative to the 

 important influence exercised by phosphoric acid 

 upon the growth and fullest developement of 

 plants, with statements of the proportions in 

 which phosphates exist in different grains and 

 other agricultural crops. The extent of the de- 

 mands made upon the soil for the phosphate of 

 lime, by growing animals kept upon it, have 

 been estimated by Mr. Hayward, a skilful che- 

 mist. He calculates the amount of phosphoric 

 acid annually abstracted by the live stock from 

 a farm of 100 acres, to be equal to 413 Ibs., re- 

 quiring to produce it 1491 Ibs. of bones. His 

 estimate is as follows : 



In the bones and flesh of 110 lambs, of Acid. Bones. 



25 Ibs. euch, at 6 weeks old . . 145 537 



In 40 year-old sheep, of 90 Ibs. each . 210 777 

 In 4 calves, at 5 weeks old, weighing 



together 500 Ibs 21 77 



In 4 young cows, forming 135 Ibs. flesh 



and 35 11)8. of bone each per annum . 16 23 

 In 2 young horses, gaining the same as 



the last . . . . . .21 77 



Phosphate of lime consists of 59 parts phos- 

 phoric acid, and 47 parts lime. The phosphates 

 of magnesia, potash, and soda, are found much 

 less extensively in agricultural products than 

 the phosphate of lime, which last seems indis- 

 pensable to fertility. The chief modes in which 

 the farmer has long been accustomed uncon- 

 sciously to return this salt to the soil has been, 

 by the use of oil cake for his stock and of crushed 

 bones for manure. In a more recent period the 

 use of guano, of urate, &c., has been in fact a 

 similar operation. It has been found by Pro- 

 fessor Johnston (Trans. High. Soc. 1845, p. 

 470), that turnips grown upon land dressed with 

 guano contained a considerably larger proportion 

 of phosphate of lime than the turnips grown in 

 the adjoining soil, dressed in the ordinary way, 

 the ashes of the turnips grown with the ordinary 

 farm-yard dung containing 7-73 per cent, of 

 phosphoric acid, whilst the turnips produced 

 on the land manured with guano yielded 19-39 

 per cent. 



Perhaps the most economical plan by which 

 phosphoric acid can be introduced into the soil 

 is through the application of superphosphate of 

 lime, the process of preparing and applying 

 which will be found described under the head of 

 BONES. Of bone-dust, 40 Ibs. to an acre, Liebig 

 considers sufficient to furnish the necessary sup- 

 ply of pr.osphates to 3 crops of wheat, clover, &c. 



Oil or linseed cake is not only valued by 

 English farmers as food for stock, but, as we have 

 previously stated, as a dressing for land. It has 

 been usual to attribute its good effects in pro- 

 moting the growth of plants mainly to the oil ; 

 but as this exists in small proportion, and as the 

 eff'-rt* of oily manures, such as blubber, fish, &c., 

 only last a single year, wlif-rea* those of linseed 

 eakp endure for several years, its fertilizing 

 effects must depend upon some other ingredient. 

 In 3 specimens of linseed cake analyzed by Mr. 

 Gyilp. hp found respectively 12-4, 10-5, and" 8 per 

 cent, only of fatty matters. The ashes or solid 

 portions of 3 varieties of oil cakp, examined by 

 Mr. Fromberg, were found to contain ppr cent, 

 of earthy phosphates: 1st, Gold of pleasure, 

 aO-56; 2d, English cake. 47-67: and 3d, Ameri- 

 can cake, 38*28; fthe ashes constituted of the 

 890 



1st cake 6-89, of the 2d 7-25, and of the 3d 6-35 

 per cent, of the entire cake.) 



The phosphates of lime, magnesia, soda, &c., 

 which abound in the urine of man, the swine, 

 and other omnivorous and carnivoious animals, 

 are not met with in that of the ox or horse, which 

 last discharge all their phosphates with the solid 

 excrements. The super phosphate of lime, as 

 prepared for sale, ought to contain, when genu- 

 ine, in 100 parts, according to Mr. Pusey, phos- 

 phate and biphosphate of lime 35 to 40 ; Sulphate 

 of Hme or gypsum 20 to 25; animal matter 20; 

 water 20 parts. It has often, however, other 

 substances mixed with it which reduce its value, 

 and of these plaster of Paris is one of the most 

 common. Its price in England is about 7 shil- 

 lings, or $1.75, for 112 Ibs. 



In an experiment where about 6 cwt. of 

 superphosphate of lime was applied to wheat, 

 ploughed in at the time of sowing, the produce 

 on the acre was over 53 bushels of 61 Ibs. each; 

 whilst an acre sown with 400 Ibs. Peruvian 

 guano, the ensuing spring yielded 40 bushels, 

 and the soil without any dressing, about 29 

 bushels per acre. Hence it appears probable, 

 that weight for weight, it is fully equal as a fer- 

 tilizer to the best guano. 



PIGEON (Columba). All the numerous va- 

 rieties of this domestic bird, such as tumblers, 

 carriers, powts, &c., come from one common 

 species the stock-dove which derives its name 

 from building in the stocks of trees. 



PIGEON'S DUNG. See DOVE-COTE and 

 GUANO. 



PIGGERY. A collection of small sties where 

 hogs or swine are lodged. See SWINE. 



PIKE. A word of various signification in dif- 

 ferent districts. In some counties it is applied 

 to a prong, or what is generally called a fork, 

 used for carrying straw, &c., from the barn, 

 cocking of hay, &c. In others it signifies a sort 

 of stacklet or load, cock of hay, &c. In the 

 midland districts of England it means to glean. 



PILE. A sharpened beam of wood driven 

 down into the ground to protect the banks of 

 rivers, or for other similar purposes. Pile is 

 also provincially applied to the breaking off the 

 awns of thrashed barley, and to a blade of grass. 



PILING-IRON. A tool used in breaking off 

 the awns of barley, and sometimes the tails of 

 oats, an operation which with the farmers is 

 called piling barley. See HUMMELLER. 



PILEWORT CROWFOOT. See CROWFOOT. 



PILLWORT (Pihilaria, from jri.lula, a pill; 

 shape of the heads containing the reproductive 

 organs). The creeping pill-wort, or pepper- 

 grass (P. globie/ifera), is in England an obscure 

 little plant, found in dark meadows among grass, 

 especially where they have been overflowed 

 with water during winter. It is perennial in 

 habit, putting forth brown flowers in June and 

 July. 



PIMPERNEL (Anagallis). A genus of very 

 pretty, interesting plants, of easy culture. 



PINE TREE (Piuus, from pinos ; a Greek 

 word used by Theophrastus, to designate a pine 

 tree ; and some authors derive it from the Celtic 

 pin or pyn, a mountain or rock, alluding to the 

 habitat of the tree). This much-esteemed and 

 well-known genus, belonging to the gymno- 

 spermous division of exogens, contains some of 

 the trees of most universal use in civilized so- 

 ciety, and which form a very important article 



