January i, 1885.] 



THE TROPICAL AGRICULTURIST, 



535 



all, among the broad green leaves appears the blossom, of a 

 rich purple colour. The blossom opens, and inside is seen 

 the stamens, to which the young fruit are attached. The 

 upper portion of the blossom serves as a cap to protect the 

 fruit from the direct heat of the sun until it is sufficiently 

 matured to ripen unprotected. When the fruit is gathered, 

 the branch of the banana upon which it has grown is cut 

 down and laid at the root, and a new plant springs up. We 

 were also shown some date palms, but they were not bearing 

 at the time. The curious fact^-that is, of course, to laymen 

 — of the division of the pahns, coconut as well as date, into 

 sexes was explained to us. The pollen of the blossom of the 

 male tree is carried by insects or by the wind to the flower 

 of the female tree, where in due course it fructifies. The 

 paupau tree, or mammy apple, was another curiqsity to us. 

 It bears a fruit gathered in a cluster beneath the crown of 

 foliage surrounding the tree. This fruit somewhat resem- 

 bles in appearance the melon ; and indeed is, in colour and 

 flavour, not unlike the rock melon. It is stated 

 that if a piece of tough meat is hung on its branches, the 

 meat will become in a short time quite tender.— Sydney Mail. 



AMOUNT OF OIL IN LINSEED CAKES. 

 (To the Editors of the " Tropical Agriculturist") 



London, Nov. 7th, 18S4. 

 Gentlemen, — The enclosed is a printed copy of a 

 short paper I have prepared for the Irish Farmer news- 

 paper, and which has been favourably received here by 

 all parties interested in the purchase of Linseed Cakes, 

 inasmuch that too much importance had been placed 

 upon the amount tf oil, whereas the hard-pressed 

 western cakes of America have been found by farmers 

 to give excellent results as a cheap feeding cake. I 

 thought you might like a copy for your paper or the 

 Tropical Agriculturist. — Yours very truly, 



John Hughes. 



At the present time stock feeders are busy preparing 

 for the winter markets, and the selection of the most profit- 

 able feeding materials is a matter demanding careful con- 

 sideration. 



With Wheat so cheap and in such good condition as it 

 is this year, many shrewd, practical men will probably con- 

 sider it more economical to employ it when crushed as 

 a partial substitute for some kind of Oil Cake, and thus 

 make their wheat crops literally walk to market. 



Be this as it may, a certain quantity of good Linseed 

 Cake will no doubt be required as usual, for long experience 

 has firmly established the superiority of this Cake over 

 those made from Rape or Cotton Seed, and its market 

 price influences that of all others. Indeed, the price of 

 Linseed Cake is far more constant than its composition, 

 specimens of very different quality being frequently offered 

 at the same price by rival merchants, and it is to be regretted 

 that samples are not accompanied by a guarautee as to 

 chemical composition, in the same manner as artificial 

 manures are sold. If this were done, farmers would know 

 more about the quality of their feeding cakes, and would 

 be able to trace the cause of their stock doing so much 

 better on one kind of cake than on another. 



At present Linseed Cake is usually purchased according 

 to the brand, some manufacturers taking more oil out of 

 it than others, according to the pressure exerted and the 

 character of the seed operated upon. Manufacturers who 

 are careful always to purchase well-matured Linseed, of 

 good quality, free from dirt, and with only a small pro- 

 portion of foreign weed seeds, naturally acquire for their 

 brand of cake a well-earned reputation and an enhanced 

 price. The amount of oil left in the cake will, of course, 

 vary according to the market juice of Linseed Oil, for it 

 must be remembered that the cake is a "residual product," 

 the manufacturer's primary object being to extract the oil, 

 and that he only allows a certain proportion to remain in 

 the cake because it pays him better to do so than to employ 

 greater pressure and extract more completely. 



This variation in the quantity of oil left in the 'alec has 

 led many persons to attach an undue importance to its 

 presence as an exact indicator of the general feeding value 

 of respective samples, and to forget that the nutritive value 

 does not depend solely upon the proportion of fatty 

 ingredients, but also, and to a very considerable exb u 



the large quantity of albuminous (flesh-forming) compounds, 

 mucilage, and digestible fibre which should exist in all good 

 cakes, and further, to the special readiness with which these 

 constituents are likely to be assimilated. Moreover, the 

 proportions of woody fibre (or cellulose) and dirt in the 

 form of sand are most important factors to be considered 

 when determining the probable digestive character of any 

 particular sample of cake. Lastly, the amount of moisture 

 is important, for with a high percentage the cake, if kept 

 in a badly ventilated place, is very likely to get mouldy, 

 whereas a dry, hard-pressed cake can be kept for mouths 

 under ordinary circumstances in excellent condition. Thus 

 it will be seeu that in order to give a reliable opinion upon 

 the quality of a cake, a- full analysis, and not simply a 

 determination of the amount of oil, is necessary to be made 

 and we must consider all the points of importance if a 

 correct judgment is to be arrived at. 



Linseed Cake comes, it is true, under the general title 

 of an Oil Cake, in the same way as Cotton or Rape, 

 because it is a cake made from the residue of a seed' 

 rich in oil, and not because oil alone is to be considered 

 its principal feature as a feeding material. Of late the 

 manufacturers have thought it economically desirable to 

 introduce improved machinery, and by pressing harder 

 have reduced the percentage of oil from about 12 or 14 

 to 10, and in some cases as low as 7 per cent in the cake- 

 consequently the proportion of oil has become quite a vexed 

 question, and Dr. Cameron, at a recent meeting of the 

 Royal Agricultural Society of Ireland, read a paper on 

 the nutritive value of Oil Cakes, in which he specially 

 pointed out the marked reduction in the quantity of oil 

 now present in Linseed Cakes. He stated that since 1880 

 the average amount in samples submitted to him rarely 

 exceeded 10 per cent, and sometimes fell as low as 6 per 

 cent, and it seemed absurd that special brands which still 

 contained 11 to 12§ per cent should be sold at the same 

 price as those containing only 6 to 9 of oil. Dr. Cameron 

 actually proposed that 10 per cent of oil should be con- 

 sidered the minimum amount of that ingredient which 

 should entitle a Linseed Cake to be sold at the current 

 price of that article, and suggested that for every 1 per 

 cent less than 10 there should be a reduction of 5 per 

 cent from the price. For example, if the current price 

 of good Linseed Cakes was £9 10s. per ton, then a cake 

 containing 9 per cent of oil should be sold for £9 0s 6d 

 and a cake having only 8 per cent for £8 lis. per ton ; 

 in other words, a deduction of 9s. 6d. for every 1 per 

 cent of oil under 10. 



Now this deduction seems to be far too much and is 

 purely empirical, as we have no practical feeding experi- 

 ments available upon which to establish reasonable grounds 

 for assuming that the loss in the feeding value of a cake 

 is in proportion to these figures. Dr. Cameron does not 

 say that an equal addition should be made for every 1 per 

 cent of oil above the minimum of 10, and he was wise 

 in refraining from doing so, for at 9s. 6d. per unit a ton 

 of Linseed Oil would cost £17 10s., whereas, the present 

 market price is only about £22, or 4s. 4Jd per unit. 



1 submit that it is not usual to value the presence of 

 a comparatively small quantity of an ingredient such as 

 oil in a bulky material like cake at a higher rate per uuit 

 than it cm lie purchased in the concentrated form of 

 Commercial Linseed Oil. 



If the feeding value of Linseed Cake depended solely 

 upon the proportion of oil contained, surely cake» would 

 limy since have been sold at prices regulated by the 

 percentage of oil which they were found on analysis to 

 contain, or we should have used the pure oil itself sprinkled 

 over the cut food. 



According to Dr. Cameron, two cakes otherwise equal 

 as regards the amount of albumenoids, mucilage, and 

 digestible fibre, but containing in one case 7 per cent 

 of oil, and in the other 10 per cent, should respectively 

 be sold for £8 Is. 6d, and £9 Ills. 



Assuming, as I have said, that both cakes are equal in 

 other respects (and this can readily be ascertained by 

 making a careful analsyis), it appears reasonable to conclude 

 that the farmer will find, it more profitable to purchase 

 the cake containing 7 per cent of oil at £8 Is oM., or if 

 he wishes he can expend this sum in buying more cake 

 of the same quality, so that in one case he will h*ve 1 

 ton 3j cwt. against 1 ton. 



