Vol. XVI. No, 404. 



THE AGRICULTURAL JTEWS. 



323 



be carried out primarily in the laboratory. But what 

 is discovered in the laborator}- holds good in the field. 

 From careful laboratory experiments the following 

 conclusions were arrived at: — 



1. The loss of nitrogen from a manure heap is 

 partly due to three causes: (a) the washing away of 

 soluble substances; (b) the volatilization of ammonia: 

 (c) the liberation of some other gas, presumably 

 gaseous nitrogen. 



2. These losses begin as soon as the air is allowed 

 to enter the heap, and they become more intense as 

 the temperature riscf. 



3. The losses do not take place when air is com- 

 pletely excluded from the manure. 



4. When air is completely excluded, and the 

 temperature is caused to rise, not only is there no 

 loss, but a distinct improvement in qunlity takes 

 place. 



Both the laboratory analyses and field experi- 

 ments thus show that exposure to atmospheric 

 influences causes a loss in quantity and quality of the 

 manure. No manure heap, however, has yet been 

 made which will absolutely meet the conditions of 

 conclusions 3 and 4. Still it is clear that it is to the 

 advantage of the farmer to endeavour to store his 

 manure in such a way as to approximate to those 

 conditions as nearly as possible. 



The common, method of making up manure in the 

 open with no shelter over it must be condemned, as 

 most surely causing very considerable loss in quality- 

 There is no question but that some shelter from rain is 

 most necessary, and that the heap should be com- 

 pacted as closely as possible. In all cases special care 

 must be taken of any liquid draining away from the 

 manure heap. Some kind of a tank ought to be made 

 to hold it. This liquid should not be poured back on 

 the manure except just before spreading, but it ought 

 to be applied to the land separately. The use of this 

 and of urine as liquid manure produces excellent results. 



Even with these precautions it is still certain that 

 large wastage takes place at present in the making and 

 storing of farm-yard manure. The laboratory experi- 

 ments show that not only can manure be stored with 

 out loss, if air and water are completely excluded.but that 

 positive gain in quality is produced, if, in addition, the 

 temperature is raised. The conclusion, therefore, is that 

 the only method of excluding the air in practice would be 

 to store the manure in air-tight tanks or pits. 



In the West Indies the question of increased 

 temperature is arranged for by nature. The details- 

 of construction of such tanks or pits would have 

 to be carefully worked out, so as to discover how 

 far the gain in fertilizing power of the manure 

 would counterbalance the expense of such a tank 

 or pit. It would seem however, that any attempts 

 to avoir! loss in making and storing manure will 

 Tiave to be on these lines, and the possible gain to 

 the farmer makes it a subject worth most careful 

 attention. 



POSSIBLE USES OF BY-PRODUCTS 

 OF THE SUGAR INDUSTRY. 



An article in the Louisiana Planter, August 

 2.5, 1917, under the above heading gives an outline 

 of feeling in Hawaii on tlie subject. It says that 

 the Hawaiian Planter s Record thinks that there are 

 possibilities involved which should be considered at 

 a time like this. Such possibilities might also 

 deserve consideration bj' those who are interested in 

 the sugar industry in the West Indies. 



The following data are given: The potash alone contained 

 in the molasses that the Hawaiiaas produce each year 

 amounts to about .5,100 tons. The value of this at the 

 present time would be approximately •?2,.5.50 000, or under 

 normal conditions, .t^-SlO.OOO. Under normal conditions- 

 they import each year about 4,800 tons of potash for fertili- 

 zer. The potash in their mo:asses, therefore, is 300 tons 

 in excess of their annual importations of this miterial. 

 The same is true to a lesser extent of nitrogen and phos- 

 phoric acid. In manufacturing potash from molasses an 

 additional value may be obtaihed in the form of fuel either 

 direct or as alcohol. 



One ton of molasses will prorl ace 60 gallons of alcohol, 

 now worth approximately $36, or COc. a gallon. Under 

 normal conditions its value would be .$1980, or 33c. 

 a gallon. Used as a substitute for gasolene it would be 

 worth "512, or 20c. a gallon. When properly handled alcohol 

 is equivalent, gillon for gallon, to gasolene. The residual 

 potash left over from the manufacture of alcohol from 1 

 ton of molasses is 80 lb. At the present market price this 

 would be worth S20. Under normal conditions it would bq 

 worth v"!. 



I The fuel value of the annual Hawaiian output of 

 molasses is equivalent to 2-5,500 tons of coal. The fuel 

 value of 1 ton of molasses is equivalent to 1 ton of 

 bacasse, or \ of a ton of coal. The potash contained in 

 1 ton of molasses which could be recovered on burning 

 is 64 lb. (80 percent, recovery). This is worth, at the 

 present market price, 91&. or 25c. per BE). Under normal 

 conditions it would be worth •$3-20, or 5c. per lb. 



In connexion with the question of employing 

 molasses as a source of industrial alcohol to take the 

 place of petrol as a fuel, the Australian Common- 

 wealth Advisor}' Council of Science and Industry 

 draws attention to the fact that the cheapest source 

 for the production of such alcohol in Australia is sugar 

 molasses. We publish in another column the report 

 of the Committee of that Council appointed to deal with 

 the subject. 



