Vol. IX. No. 211. 



THE AGRICULTURAL NEWS. 



163 



inferior Juic-e. For the purpose of the investigation of the 

 efl'ect of such increased pressure, the cane is regarded as being 

 divided into rind, nodes and interior jiitb, not because of any 

 botanical significance, but for the purpose of introducing 

 simplicity into the consideration of the subject. 



After a brief review of previous work on the structure of 

 the sugar-cane has been given, the author proceeds to outline 

 the method of division of the cane which he emiiloyed in 

 practice. The procediue was to saw through the node, on 

 each side of its widest part, on the outer line of the region 

 from which the adventitious roots spring, and to strip the 

 internode, thus separated, of the rind. The rind was not 

 separated from the node, so that this portion consisted chiefly 

 of rind, fibro-vascular bundles and a certain amount of pith. 

 The ditt'erent parts obtained in this way were then analysed 

 in order to find their content of moisture, fibre, solids and 

 sucrose, the fibre being determined by difference. I'sing the 

 varieties Rose Bai'iboo, Yellow Caledunia and Lahaina, the 

 figures for the last two being obtained from cane grown in 

 two diti'erent places, the following are the means of the 

 highest and lowest results obtained; — 



Weight, Fibre, Solids, Sucrose, Purity, 

 per 100 cane, per cent, per cent, per cent. 



Wiiole cane. 

 Weight, per 100 cane 100-0 

 Juice, per cent. Sii'-i 



Fibre 

 Solids 

 Sucrose 

 Water 



13-6 

 17-4 

 15-6 

 69-3 



Pith. 

 680 

 92-5 



7-G 

 19-1 

 18-0 



73-8 



Rind. 

 12-7 

 67-4 

 32-6 

 12-4 

 8-8 

 .54-3 



Node. 

 19-6 

 79-4 

 20-6 

 14-8 

 11-9 

 64-3 



The actual figures from wliirh the above means are 

 calculated were then employed to find others, which are given 

 in a table. The statistics contained in this are again used 

 here in giving the means of the highest and lowest results, as 

 follows; — 



As was explained in the article dealing with this 

 bulletin in the last number of the Afiricultrmil Xt-n'f, the 

 term 'absolute juice' means everything that is not left behind 

 on extraction with water. 



A further use was made of the results obtained, in the 

 direction of calculating the amount of sucro.se contained in 

 each portion per 100 sucrose of cane. Taking the means of 

 the outside results, as before, the sucrose, per cent, on sucrose 

 in cane, is found to be : pith, 77(>; rind, 7-.5; node, 14*.S. 



Having regard to the purity of the juice in these difterent 

 parts of the cane, it was possible to find the distribution of 

 the available sugar in the cane, so that, taking again the 

 means of the extreme results, the availaVile sugar, per cent, 

 on available sugar in cane, is : pith, 8] • 1 : rind, 5-8; node 1 32. 



It if pointed out that the results show that the [lart 

 which has been considered as node has a composition which 

 is intermediate between those of the pith and the rind, so 

 that the cane may be regarded as being made up of a soft, 

 interior portion composed of a small amount of fibre and 

 a juice of high purity, and of a hard, outer portion contain- 

 inf much fibre anil a juice of low purity. If, then, the part 

 which has been called 'node' is divided equally between the 

 pith and the rind, the average compcsition of the canes 

 employed in the experiment must be as follow* : — 



Following on this, an attempt was made to trace the 

 changes that took place in these soft and hard parts during 

 their pas.sage through the mill. In practice, it was naturally 

 only possible to eti'ect a rough separation into two parts, one 

 consisting mostly of pith and one made up chiefly of rind, 

 and the method did not eliminate the error that must per- 

 force accrue through the retention of juice from the soft 

 portion by the rind. Taking, as before, the means of the 

 extremes, but with three canes grown in four places, in this 

 instance, the following table may be constructecl ; — 



Pith megass. Rindmegass. 



Expressed juice. 



Weight, per 100 cane 678 



Solids, per cent 21 '0 



Sugar, „ „ 19-2 

 AVater, „ „ 

 Fibre, „ „ 



Puiity 88-9 



The next step was to find the extraction that took place, 

 from the harder and softer parts of the cane, in its passage 

 through a train of mills. In this process, the megass had 

 to be separated by hand into the two representative portions, 

 so that the division was somewhat in;perfect. The following 

 table shows the results of the analysis that are given, to one 

 place of decimals; — 



.Rollers in Train 12 12 12 1.5 12 15 



No. of Mill I. II. III. III. IV. V . 



Pith megass — 



Weight, per 100 megass 53'3 48'6 



Sucrose, per cent. 11 '3 7'2 



Fibre, „ 336 41-6 



Piind megass — 



Weight, per 100 megass 46'7 51"4 



Sucrose, per cent. 9'1 7'1 



Fibre, „ 35-2 41-5 



Whole megass — 



Weight, per 100 megass 100 1000 



Sucrose, per cent. 103 72 



Fibre, „ 34-3 41-6 



500 48-.5 51-3 50-0 



3-8 3-9 2-9 2-7 



4.5-G 46-8 46-9 494 



50 51-5 48-8 .50 



4-3 4-7 41 3-6 



44 9 45-9 46-7 48-6 



1000 1000 100 100-0 



41 4-3 3-5 31 



45-3 46-0 46 9 49-0 



The following methods are suggested for obtaining an 

 increased amount of sugar from the rind: — 



(1) Higher pre.ssures, resulting in the greater rupture of 

 the rind tissue, and giving at once a higher expression and 

 a material more suited for the absorption of water. 



(2) The obtaining of more eftective disintegration of the 

 rind tissue by the use of knives, shredders, crushers, or 

 heavily indented rollers. 



(3) The application of the maceration water by means 

 of injectors, as has been suggested recently by Pellet, instead 

 of by a perforated pipe; or by the use of macerating baths 

 through which the megass is drawn. 



Finally, evidence is adduced to show that the best 

 results will be obtained by the employment of higher 

 pressures, and attention is drawn to the fact that the milling 

 qualities of a cane do not depend merely on its content of 

 fibre, but on the distribution of this throughout the cane. 



