05" 



THE TROPICAL AGRICULTURIST, 



[June t, i? 



IMPROVED SIRO00O TEA DRIERS 

 are thus noticed in the Indian Planters' Gazette:— 

 The season for the purchase of tea machinery having 

 returned, the different makers have come forward with 

 she results of their labours towards improvement, with 

 which they have boen occupied during the, to them, dull 

 teason. Mr. S. 0. Davidson has been hard at work on his 

 •'Siroccos," and has completely revolutionised the whole 

 character of his Driers; yet so ably has this been done 

 that possessors of his old " Siroccos " of the " No. 1 ' and 

 " No. 2 B " class can convert their Driers to the new 

 system at the trifling cost of £23 for the new material, 

 and a few hours' work, and thus increase the working- 

 capacity of their Driers by two- thirds. A few extra 

 trays are also required at the extra cost of 22 shillings 

 each. With characteristic enterprise Mr. Davidson has 

 brought over one of his old converted " Siroccos " and 

 two of the now types, and is exhibiting them in Grace- 

 church Street, where I have had an opportunity of inspecting 

 thorn. I hear that he is about to send you out an 

 illustration of a "Sirocco" set up on the new system, 

 and so I need not enter too particularly here into de- 

 scription, as the illustration, which I have already seen, 

 conveys a far better idea than could be given in writing. 

 The converting process I can, however, assure your readers 

 is a very easy matter to effect ; and with the aid of a 

 few coolies, most managers could easily perform the whole 

 operation, after the new parts have been put together 

 on the ground, in half a day without skilled assistance. 

 A new working table or machan is required, as shown in 

 the illustration, and the attendants stand on the two 

 tables, one at each end of the long drying chamber There 

 are two rows of four trays each, one row above the other. 

 The green leaf is placed upon the top tray immediately 

 above the stove. As the tray with the jmcc'a dried tea is 

 removed from the lower tray above the stove, the attendant 

 at the other cud places the vmper tray nearest to him on 

 the lower row, having pushed the other three lower 

 trays forward at one shove to make room for it. Then 

 the feeder at the stove-end pushes the top three trays 

 forward, and makes room for his fresh tray ot catt-ha 

 leaf. Once all eigh* trays are in position, there is little 

 interval between putting on the top fresh tray and remov- 

 ing the lower finished tray, so the attendants are kept 

 well occupied. Tbe heat from the stove thus strikes up 

 hot against the cuteha leaf on the top tray, as it has 

 only the thin layer of dried tea to pass through, and it 

 will be found that an equivalent in this arrangement of 

 the stages of wet and dry tea is maintained m each 

 couple of top and bottom trays. Thus when halt-dried 

 at the further end from the stove, the two about hali- 

 di-iod trays an- one above the other. And as the heat 

 from the second to the fourth tray rises, as tested by 

 experiment, almost exactlj equally all along the chamber, 

 this ensures graat evenness in the drying. A little excess 

 of temperature Is noticeable rising through the trays 

 immediately above the stove, and this has the advautagc 

 of both immediately checking the fermantation ot the 

 cuteha leaf on the top tray, and briskly finishing oft the 

 auooa tea on the lower tray. No waste heat now is lost 

 up tho chimney, and it is all dispersed from the upper 

 tour trays, hence it can be utilised for withering in machans 

 overhead. The lowest machans, however, should not be 

 less than six feet above the "Sirocco," as it is found, 

 that if too close down, it baffles the draught from the 

 trays and retards the drying, by keeping the steam down 

 over the trays. The drying-chamber takes the old trays 

 with the addition of a slight baton screwed on to each. 

 The old drying-chamber-front with the holes tor the 

 drawers is done away with, the iron-sheet of which it 

 consists, being replaced by a whole-sheet provided for 

 tho purpose. A few bricks are required to support the 

 chimney iu its new position. The new "Siroccos Nos. 

 St 4 and 5 having been constructed throughout on the new 

 principle, and having certain substantial improvements in 

 the stove, will show a great increase in outturn, even 

 over the converted ones. Iu any case in offering a Drier 

 (No 5) which ho maintains will turn out 15 to 17 maunds 

 of dried tea in ten hours at so low a price as £95 packed 

 and f o.b. at Liverpool or Glasgow, Mr. Davidson_ has 

 made a very great stride iu the advantages now offered 

 to tea planters. His enterprise is reaping good fruit, as 



he has already sold 50 " Siroccos " of the new types within 

 the past fortnight, which speaks well of the opinion held 

 concerning them by the number of planters who have 

 eagerly " rushed " to look at this the last thing in Driers. — 

 Planters' Gazette. 



0O0OAS, RAW AND MANUFACTURED. 



BY E. J. EASTES AND E. TEEHY. 



Oocoa is obtained from the seeds of Tlieobroma ( 'acao. 

 This plant is so well known that there is no need to 

 enter on a long description- of it. It is a native of Trop- 

 ical America, where it is extensively cultivated. It has 

 also been introduced into the East Indies and parts of 

 Africa and Australia, but all our important supplies are 

 drawn from America and the West Indies. 



Seeds from different cocoa districts vary considerably 

 in appearance, flavour and composition. 



As soon as gathered, the seeds, with a small portion 

 of the moist pulp of the fruit adhering, are submitted to 

 a kind of fermentation called the "sweating" process for 

 a few days. This is accomplished in one of two ways, 

 either by piling them while still moist in heaps and 

 allowing them to dry slowly in the sun, beiug turned 

 over at intervals; or by burying in the ground for a 

 length of time and afterwards drying in the sun or by 

 artificial heat. This fermentation is considered to be 

 analogous to the malting of barley, germination being 

 started and then arrested. It is during this process that 

 the alkaloid theobromine is said to be formed. This 

 sweating operation requires to be conducted witli great 

 care, as on it the flavour of the seeds depends. AVheu 

 quite dry the raw cocoa is fit for exportation. 



About 13 or 14 per cent of the raw seeds is husk, which 

 is rejected in the process of manufacture of all but the 

 very commonest kinds. The average composition of tho 

 raw seed, minus husk, is as follows, being the highest 

 and lowest of a long series of published analyses : — 



Fat 43-50 in 100 parts. 



Albuminoids 13-20 „ 



Starch, Gum, etc 15-22 ,, 



Theobromine 1-2 ,, 



Mineral matter 3-4 „ 



Moisture and other constituents 6-12 „ 



We have analysed eight samples of raw commercial 

 cocoas with the following results. The figures aro 

 calculated from the seed only, after removal of the 

 husk :— 



Moist- 

 ure. 



Oaraccas 



Oirupano 



■ .' .-nada 



Guayaquil ... 



l'ara 



Surinam 



Trinidad 



(common) ... 

 Trinidad (tine, 



San Antonio) 



4-75 

 504 

 559 

 3-68 

 4-39 

 2-55 



5-62 



472 



Fat, 



Ash. 



H,PO, 



5365 



47'3s 

 47-12 

 5297 

 5707 

 5370 



4571 



53-57 



2-70 

 3-69 

 2-81 

 3-28 

 309 

 2-44 



2-7'/ 



270 



1-30 

 1 39 



!)1 

 ■85 

 1-3 



35 



•89 

 115 



Theo- 

 brom- 

 ine 



108 



S7 

 1-42 

 1-71 

 1- 

 1-42 



I '03 



104 



The averages of the above figures give percentages 

 differing slightly from those usually stated . We find 

 tho fat rather more, and the phosphates rather less. 



The raw seeds, before manufacturing, are roasted for 

 about an hour at a moderate heat, which develops 

 the flavour, and allows them to be easily separated from 

 the shell. 



Oocoa nibs are merely the roasted seeds freed from 

 their husks, and slightly crushed. This is the purest 

 form in which cocoa can be obtained. But the nibs will 

 not make an elegant, nor an easily digestible beverage, 

 nor are they economical, the method of preparation being 

 merely to boil or simmer with water for some lime. The 

 theobromine with some colouring and ilaxouring matter 

 is dissolved out to a certain extent, the fat rises to the 

 top as an oily layer, but the valuable albuminoids are 

 almost entirely lost. There is the further disadvantage 

 ot their requiring a long time to cook. 



