515 



GUANO. 



GUARDIAX. 



548 



wine-glass. On stirring, effervescence shows its presence. Genuine 

 guano, under the same circumstances, merely allows the escape of a 

 few air bubbles. We add here the method suggested by Dr. Cameron 

 in his recently published lecture on agricultural chemistry, for the 

 detection of spurious guano. By drying and burning, Peruvian guano 

 should lose from 55 to 60 per cent, of its weight. Its ash should be 

 white, and should dissolve readily, and without effervescence, in dilute 

 muriatic acid, 'leaving insoluble residue, which should not amount to 

 more than 2 per cent, of the weight of the guano. Mixed with quick- 

 lime it should give a strong ammoniacal odour. A bushel of guano if 

 pure weighs almost exactly 70 Ibs. ; if adulterated with clay, marl, 

 sand, &c., the weight will be materially increased, and so far as this 

 test applies gross adulterations will be easily detected. 



The great cost of guano has materially checked its consumption, and 

 it will be seen from the following table how much during the past 

 year its consumption has fallen off. The fact is, that at the price of 

 131. per ton many other manures are cheaper. 



The following is a table of the imports since its first introduction : 



Tears. 

 1841 

 1842 

 1843 

 1844 

 1845 

 1846 

 1847 

 1848 

 1849 

 1830 



Tons. 



2,881 



20,398 



30,002 



104,251 



283,300 



89,203 



82,392 



71,414 



83,438 



116,923 



The subject of the relative value of fertilising ingredients in guano, 

 and in other manures, has been largely discussed. Professor Anderson 

 of Glasgow, at a meeting of the Highland Society, stated the following 

 figures to indicate, according to the authorities named, the value per 

 ton of the principal ingredients as obtainable in guano : 



These are the prices at which these several ingredients are purchased 

 in guano at present prices. Can they be procured elsewhere at a 

 cheaper rate ? The ammoniacal liquor of the gas works, after having 

 been once distilled, can be obtained containing 20 per cent, of ammonia 

 at a price which gives that substance at from 3d. to 3^d. per lb., or 

 about 281. per ton. The objection to its use is, that the ammonia 

 exists there chiefly as carbonate, and in that state is peculiarly liable 

 to loss by evaporation. It is clear, however, that if concentrated gas 

 liquor were applied to the soil, the farmer could afford to lose one- 

 third of it, and still have his ammonia cheaper than in the state of 

 sulphate. The application should be of 2 to 3 cwts. per acre on grain 

 crops, both alone and mixed with a certain quantity of bone ash, and 

 the land should be made up in ridges, and the solution, diluted to a 

 proper extent, poured into the bottom of the furrows, while the 

 plough, immediately following the application, should be made to 

 divide the ridge and cover the ammonia. This should be done several 

 days before sowing, for it would not answer to put the seed near the 

 strong ammoniacal fluid, and a few days should be allowed for it to 

 disseminate itself through the soil. One hundredweight and a h;ili 

 of the ammoniacal fluid, and the same quantity of bone ash, might also 

 be tried on turnips, and should these applications prove successful, it 

 will be possible to make a mixture as good as Peruvian guano at a 

 cost of not more than 61. per ton. 



Mr. Finnie, of Swanstone, has recently called attention to the 

 existing wastefulness in the use of guano. His advice included the 

 following particulars : Government should investigate every source 

 from which a supply of guano can be obtained ; we should encourage 

 manufacturers by making trial of other portable manures ; we should 

 turn our attention more than ever to the dung heap at home ; and, 

 lastly, instead of employing guano by itself as formerly, for turnips 

 and barley, on the lighter and weaker description of soils, let fanners 

 use along with it an admixture of other manures, such as bone meal, 

 diWolved bones, or even guano of a secondary class ; and for turnips 

 and potatoes on the heavier character of soils, employ along with guano 

 some other nitrogenous manure, such as rape dust, blood manure, &c. 



Thus : Superphosphate, along with farm-yard manure, is quite a 

 sufficient substitute for guano for Swedes. Apply 3 owt. per acre, 

 along with 10 or 12 tons of dung. Nitrate of soda, 1 or 14 cwt., is 

 better applied to corn crops, if used in place of guano. 1 4 or 2 cwt. oi 

 sulphate of ammonia per acre is a good dressing for an acre of wheat. 

 If you can buy good soot at fid. to 8rf. a bushel, you can find no cheaper 

 dreeing than 40 bushels of that per acre. If you cannot get that, 



.VT'.TS AND SCI. DIV. VOL. IV. 



apply 4 cwt' f nitrate of soda and 1 cwt. of Peruvian guano per acre 

 aroadcast, in showery weather if possible. 



On the application of guano to the soil, Mr. Nesbit gives the follow- 

 ing instructions : 



(1.) Guano is best applied in damp or showery weather. 



(2.) Guano should not generally be put on grass land in the spring 

 later than April. 



(3.) When guano is applied to arable land, it should immediately be 

 mixed with the soil, either by harrowing or otherwise. 



(4.) When wheat is sown vry early in the autumn, a less than usual 

 amount of guano must at that time be applied, and the rest in the 

 spring. The wheat otherwise might become too luxuriant, and be 

 injured by subsequent frosts. 



(5.) Guano, and artificial manures in general, should be put on the 

 land only in quantities sufficient for the particular crop intended to be 

 grown, and not with the intention of assisting the succeeding one. 

 Each crop should be separately manured. 



(6.) Guano, before application, should be mixed with at least from 

 five to six times its weight of ashes, chaYeoal, salt, or fine soil. 



(7.) Guano should on no account be allowed to come in direct con- 

 tact with the seed. 



An artificial guano may be easily compounded by an admixture of 

 the constituents of natural guano, all of which, with the exception of 

 bone-dust, may be procured of any druggist. Professor Johnston gives 

 the following recipe for an artificial manure which will produce an 

 effect about equal to 1 cwt. of natural guano : 78f Ibs. bone-dust, 

 25 Ibs. sulphate of ammonia, 1J lb. of pearlash, 25 Ibs. common salt, 

 24 Ibs. dry sulphate of soda ; total, 1324 tt> 8 - 1' ne following artificial 

 substitute for guano has been successfully used, at the rate of 5 cwta. 

 per acre : 



Bones, dissolved in spirits of salt instead of oil of vitriol 18} Ibs. 



Charcoal powder . . .... about 18f 



Sulphate of ammonia (gas salt) . . . . about 9* 



Common salt ....... about 9 



Gypsum 9 



Wood ashes about 46 



Nitrate of soda (cubic petre) J8 



Sulphate of soda (Glauber salts) . . . . 10 

 Sulphate of magnesia (Epsom salts) . . . .10 



160 Ibs. 



Three or four cwts. of guano, which is the usual quantity applied 

 one acre, have often proved equal in effect to fifteen tons of farm-yard 

 dung. Mr. Lawes, an experienced agricultural chemist, gives the fol- 

 lowing table of the constituents of these two quantities : 



Folia CWTS. OP Gfixo CONTAIX 



Phosphate of limo 112 Ibs. 



Ammonia ......... 54 



Organic matter 171 



Potanh, soda 30 



FlFTMX TONS OF DtJXO COXTAIX 



Phosphate of lime 100 Ibf. 



Ammonia . . . . . . . . . 195 



Organic matter ........ 8505 



Potash, soda, and silica . .... 133] 



Experiments have indeed been made, the results of which showed 

 that 3 cwts. of good Peruvian guano were equal in their immediate 

 effect to 20 tons of good farm-yard dung ; but much is required to be 

 known of the composition of a soil, and of the crops which it is to 

 yield, before the exact value of any manure for that soil and crop can 

 be fully settled ; and this can only be ascertained by extensive experi- 

 ments under every variety of local circumstances. The question may 

 also arise, whether guano and other stimulating fertilisers do not 

 exhaust the land while they produce great immediate results. They 

 may, by supplying ingredients hi which the soil is deficient, enable the 

 plant so to use up others present in the land, that the soil shall be 

 poorer after the crop has been removed than it was before the manure 

 was applied. In this way it is that certain " artificial " fertilisers 

 are called stimulating, and that farm-yard dung is alone a complete 

 manure. 



For various crops the guano answers best after vegetation has com- 

 menced ; and it is useful in some cases to apportion the quantity 

 intended to be used per acre into two or three portions for sowing at 

 intervals, but the intervals most favourable are not fully determined. 

 For small allotments or gardens it is often most convenient to use 

 guano in a liquid state, in which case 4 Ibs. of guano may be mixed 

 with 12 gallons of water, and used after it has stood twelve hours, and 

 the proportion per acre may be from a half to one cwt. of guano to 

 160 gallons of water. 



GUARANINE (C 10 N,H 10 0,), a substance identical with theine and 

 caffeine, and found in the (juarana officinalis. [CAFFEINE.] 



GUARD is a detachment of troops appointed to watch a position to 

 prevent surprise, or to take care of stores, baggage. &c. 



GUARDIAN, one who has the care of a person and his property, 

 who, by reason of his imbecility or want of understanding, is in law 

 considered incapable of acting for his own interest. Guardians in tho 

 English law are appointed only to infants, though under the civil law 



N N 



