Vol. XIII Xo. 305. 



THE AGRICULTURAL NEWS. 



15 



(1) The normal fermentation of green manure is swamp 

 paddy soils leads to the production of a relatively large pro- 

 portion of methane, a smaller amount of nitrogen, together 

 •with some carbon dioxide and hydrogen. (2) The introduc- 

 tion of a crop so modifies the gas production that the propor- 

 tion of methane in the gas i8 greatly reduced and that of 

 nitrogen greatly increased. The evolution of hydrogen is 

 practically inhibited. (3) The action of the crop is to 

 restrict the formation of methane and hydrogen either by 

 retarding the rate of fermentation of by a portion of 

 the intermediate products of decomposition being ab- 

 solved by the roots. There is also evidence adduced 

 to show that the normal evolution of nitrogen is retarded 

 in a simple manner. (4) The soil conditions are shown 

 to be anaerobic in character immediately after water is 

 admitted to the fields, and these conditions petsist so long as 

 irrigation proceeds. Under these circumstances, nitrification 

 is impossible and nitrates produced during the dry season 

 are quickly denitrified so that the nitrngen required by the 

 crop is obtained from the ammonia and nitrogenous organic 

 compounds produced by the anaerobic decomposition of the 

 proteidi? of the green manure. (5) Certain of the substances 

 produced by this decomposition are toxic to the crop, and 

 must be removed in the drainage water, or destroyed by 

 prolonged decomposition before the seedlings are trans- 

 planted, otherwise the crop will sutler. The application of 

 green manure to badly drained areas must, therefore, be 

 undertaken with circumspection and caution. 



The following conclusions are drawn in regard to 

 the evolution of gases from the soil: — 



These investigations have led the authors to the conclu- 

 sion that the surface film of algae, etc., which covers the 

 surface of the swamp paddy soils, and which evolves large 

 quantities of oxygen, is the chief agent in causing the aeration 

 of the roots of the crops. 



The oxygen evolved by this film is dissolved in the 

 irrigation water and thus produces a very highly aerated 

 solution from which the roots derive the oxygen essential for 

 tbem. In undrained soils this solution does not penetrate 

 into the soil, and, consequently, the roots are congested near 

 the surface of the soil and the amount of soil from which they 

 derive their food is therefore limited and the crop suflfers. In 

 drained soils the strongly aerated water penetrates the soil 

 and the roots are able to penetrate to a greater depth. The 

 mass of soil from which the food supply is drawn is increased 

 and the crop benefits in proportion. 



Too great a rate of drainage decreases the formation of 

 the film and the aeration of the roots thereby lessened. There 

 is, therefore, for all swamp paddy soils an optimum rate of 

 drainage which produces the greatest aeration and this rate 

 of drainage is a comparatively slow one. 



Aeration of these soils by atmospheric oxygen is not as 

 effective in promoting root aeration as is aeration by the 

 water draining through them. 



The use of green manures in drained paddy soils induces 

 a greater activity on the part of the surface film, thus leading 

 to a better aeration of the roots. 



The above conclusions are taken from an article 

 by the writers mentioned above, in a recent number of 

 the Memoirs of the Department of AgriciUture in 

 India (Chemical Series). 



WEST INDIAN PRODUCTS. 



DRUGS AND SPICES IN THE LONDON 

 MARKET. 



GINGER. 



There has been but a very slow demand for all kinds 

 throughout the entire month. At the first spice auction 

 on the 5th, the offerings amounted to 298 packages from 

 Formosa, all of which were bought in at 45s. per cwt. fur 

 fair common and 18s. for the rest. 



NUTMEGS, MATE, I'l.MENTO AND ARROW EOOT. 



There was a steady demand for nutmegs at the first 

 auction on the 5th, when 117 packages of West Indian were 

 disposed of at the following rates: 72'3 to 78's, Qd. to 'd., 

 90's od, lOO's to llO's 4|A to ikl, Hi's to 122's Ud. to 

 4jd, and 138's to 142's 4|i. In the following week, namely 

 on the 12th, 215 packages of West Indian were offered, part 

 of which sold, CG's to 76's fetching 6d. to lOd., 78's to 3S's, 

 ')^d. to 7d., 92's to 105's ihd. to 5d. and llS's to 134's 

 if,d. to 5^d. On the 26th there was again a good supply of 

 nutmegs, namely 330 packages of West Indian, part of which 

 was disposed of at similar similar rates to the foregoing. 



Of mace, at the first auction on the 5th, 1 7 packages of 

 West Indian were sold. Is. 9ii, to Is. 10c?. being paid for fair 

 reddish. Is. 8d. to Is. 9(Z. for dark red, and Is. 5d to Is. '3'?. 

 for broken. A week later there was an increased demand, 

 and 33 packages of West Indian sold at the following rates: 

 good fetching 2s. to 2s. 3d., fair Is lie?., ordinary Is 9c?. to 

 Is. 10(Z.,red Is. 8d. and broken is. 3d to is. 7d. At the 

 last auction on the 26th mace was still in demand, some 94 

 packages of AVest Indian being offered and mostly sold at 

 slightly lower rates. At the lieginning of the month pimento 

 was in steady demand at 2^'i. per lb., but at the end of the 

 month the offerings were all bought in. Arrowroot was 

 represented at the first auction on the 5th liy 20 cases of 

 Natal, 10 of which sold at Q^d. per ft). At the close of the 

 month the offerings of arrowroot were all bought in. 



SARSAPARILLA. 



At the drug auction on the 13th, sarsaparilla was repre- 

 sented by 19 bales of grey Jamaica, 13 of native Jamaica, 

 and 5 of Lima-Jamaica. The whole of which was disposed 

 of, except the Lima-Jamaica, none of which found buyers. 

 Of the grey Jamaica, Is. Id. to Is. 9d. per B). was paid for 

 fair part chumpy, and Is. Qd for .sea-damaged. The 13 bales 

 of native Jamaica realized lOd. to 10 id. per lb. for dullish 

 to fair red and 9d. for common dull. A fortnight later, namely 

 on the 27th, only small qualities of sarsaparilla were brought 

 forward, namely 11 bales of Lima-Jamaica, and one bale of 

 native Jamaica. The whole of the former was disposed of 

 privately, and of the latter \ld. per tt). was paid for dull red_ 



TAMARINDS, LIME OIL, LIME .TUICE AND KOLA. 



It was reported in the early part of the month that 

 a large quantity of East Indian tamarinds had been sold 

 privately, and that West Indian were getting scarce and 

 not obtainable under 15s. 6d., in bond or 16s. duty paid. 

 Quantities of both lime oil and lime juice were reported at 

 the end of the month to have arrived, namely, of the 

 former, 15 packages from Dominica and 62 from Montserrat, 

 and of the latter some 500 packages from Dominica. At 

 auction on the 27th, 88 packages of kola were offered and 

 13 sold, Sd. to 3|rf. being paid for fair small to bold 

 dried West Indian. Darkish realized '2^d., and slightly 

 wormy 2d. per B). 



