6So 



THE TROPICAL AGRICULTURIST. 



[Ma^ci^ T, ,;???4. 



"We need not look for the advantage of drawing down 

 to lie in the gravitj- of the steamy air, as, while it is 

 in tlie condition to hold the maximum quantity of vapour, 

 it is in a condition to rise, as well. 

 I quote from a standard work on the subject ; — 



"Tension of vapours.".... ...The maximum 



density of vapours is dependent on the temperature ; 

 it increases rapidly as the temperature rises. This is 

 well shown in the case of water. Thus, talcing the specific 

 gravity of atmospheric air at 100 ° O. or -212 ° F.=i,OIIO 

 that of aqueous vapour in its greatest state of compression 

 for the temperatures will be as follows : — 

 Fahrenheit. Specific Gravity. 

 32 ° 5.600 



60 , 14,108 . 



100 46 .500 



150 170,293 As above air. 



212 625,000 1,000 



I think, from the above figures, that a moderate temper- 

 ature witli a quick circulation will be found best for 

 drying ; and that the air must be discharged while hot 

 enough to carry off the v.apour economically. It is quite 

 clear that the air is hot enough to rise very rapidly. 

 When it is charged with all the vapour, possible, to be 

 .safely taken from most fruits, seeds, &c., likely to require 

 drying by this means. Probably about 100° F. is 

 about the heat that may be safely used for general purposes. 

 At 120° coffee was bleached by the "Oerihcw, " which 

 likely led to the abandonment of that form of drier. I 

 suspect there had been a great want of circulation from 

 malconstruction, resulting in a sort of low stewijiij. A high 

 temperature with the attendant vapour would be sure to 

 bleach some of our products. AVaut of circulation with too 

 low a temperature might induce a sort of fermentation. 

 These remarks refer to ordinary drying. 



One more point, which " J. B." may think of. It is 

 obviously wrong to c^raw vapour through what is already 

 dried, or even through the materials being dried. If we 

 can get each surface to clear off its own vapour, the greatest 

 effect, will be obtained. This is so far met in tbe " Drier " 

 by keeping the temperature a little higher at the furnace, 

 end with a freer influ.\ of air, then the current of vapourous 

 air is pretty equally drawn alony the si.\ tloors, and neither 

 ** up" nor " down " altogether, but up and along. Apo- 

 logizing for taldng so much valuable space, I am. yours 

 faithfully, WM. CAMEKON. 



TEA AND CACAO IN TRAVANCOEE. 



Travaucore, 22acl Feb. 1S84. 



Sir, — In your overland issue of the 7th inst. yon 

 refer to giant tea bushes on Abbotsford. It may inter- 

 est your readers to know that Travancore is not 

 far behind. When spending a short holid.aj' there last 

 month, I have seen a tea tree measurinc; in heiqht 

 23 feet 5 inches, and girth of stem close to the ground 

 27 inches, and two feet from the ground 22 inches. 

 These ineaturements, you will allow, compare favor- 

 ably with the Ceylon giants. The Travancore planters 

 are beginning to wake up to the necessity of having 

 more than one string to their bow, and are now going 

 ahop.d with tea: the older and moro " canny " ones 

 prefer giving it a fair trial in virgin soil to planting 

 up the existing coffee land ; the latter, no doubt, is 

 more economical, but as to future results, I should 

 think, bear no comparison to the former. 



Cofl'ee prospects are, so far as I could judge, favor- 

 able, and I tliink there will be tairly good crops 

 all round. Ijealdisease h.as been knocking about as 

 usual, but hasnot done moredamagethanon previous years. 



Cacao promises exceedingly well, and will, I believe, 

 be a gre.it success. I have seen some trees 3J years 

 old, with 10 to 30 pods ou each. 



The railway survey through the Ariankow Pass is now 

 being pushed on rapifily and will very soon 

 be complete. There is an alternate route via 

 Xagercoil in th e south. The I ravancore Govern- 

 ment have not yet decided which to accept, but every- 

 one with any knowledge of the country give prefer- 

 ence to the latter. —Yours, &o., TRAVELLER. 



CINCHONA BARK: DISCREPANCY BETWEEN 

 COLOMBO AND LONDON ANALYSES. 



Colombo, 1st March 18S4. 

 . SiK,— In September last a small parcel (1,280 lb) 

 cinchona officinalis sbarings from BallaeoUa Ella, 

 Haputale, was analysed in Colombo, andthe result 

 stated as 1-09 per ceut crystallized sulphate of quinine. 

 The bark w.ts shipped in the " Duke of Suther- 

 land " and sold in Mincing Lane at one sMIling p;r 

 lb._, a very high price for the reported quality." 



I wrote for analyses, if possible, and, as the'sample 

 had beeu preserved, received it by the mail yesterday. 

 It results according to Dr. Paul in 22 percent of 

 crystallized quinine sulphate, just over double the 

 Colombo yield, besides 0-74 per cent of crystallizetl 

 einohonidine sulphate. Annexed is copy of Dr. Paul's 

 analyses.— Yours truly, 



SYLVESTER T. RICHMOND. 



(.Vop!/.) 



Dr. B. H. Paul, Analytical Laboratory, 13, Fen- 

 Consulting Chemist church Avenue E. O., and 1, 

 and Victoria Street, Westminster 

 Commercial Analyst. S. W., London 29th Jan. 1884. 



CINCHONA BAEZ CEHTIFICATE. 



To Messrs. 0. M. & C. AVoodbouse & Co., 30, Miucing Lane. 

 The sample of tinchona bark received from you on the 

 24th inst. marked Ballagolla Ella ex " Duke of Suther- 

 laud " gives the following results on analyses : — 



1 lb. (7,000 grains) of the bark, 

 per cent. contains. 

 Crystallized quinine sulphate 2-20 154 grains 



Crystallized ciuehonidine sulphate 074 51J „ 



Cinchouidiue (alkaloid) trace 



(Signed) Ben. H. Paul. 



Tea PREPAK.1TI0N IS China.— The ten haf is the 

 same pretty well ail over China, unless it be in the 

 south-western districts in and bordering on Yiiunau". 

 The great tea-producing districts are however farther 

 north, bordering in the Yangtszekiang and extending 

 far into the interior. '1 he small garpen proprietors and 

 farmers cultivate, gather the leaf and prepare it suffi- 

 ciently for tr.ansport to the coast by native dealers, 

 who go round buying up the produce on the spot. At 

 the Treaty Ports, the European merchant buys from 

 from large dealers, who refire the tea, assort it i 'o 

 grades and otherwise manipulate it. In fact, the 

 "godown" manipulation is supposed to be the most 

 important part of the tea breparation, differant fl.ivours 

 being produced at will, while the Chinese as wp kuow 

 are experts at adding colouring matters in order to 

 give tea the handsome glo.ssy "face" popular in some 

 quarters ; while it is well-known now all over the 

 world, how freely they would they would, and do, 

 adultetate, if left to themselves. Experts among Euro- 

 peans, however, now find it most profitable to give 

 their attention chiefly to really superior carefully- 

 prep.ared and highly-flavoured teas as affording the 

 most cbancaof a protitahle return. In Conton, teas .ire 

 artificially flavoured by flowers gathered from a var:ety 

 of jasmiue producing the white fragrant blossom fnm'- 

 liar to U3 in Ceylon. A layer of tea is placed in iho 

 bottom of a large basket and a few flowers scwttered 

 upon it. then auother layer of tea and another l.iyer 

 of flowers, and so on until the basket is full. Tiie 

 flowers are t'onerally placed in the tea in the after- 

 noon and allowed so rom.ain there overnight, when it 

 is found that the tea are absorbed most their fragrnce. 

 The flowers are removed by sifting, and the tea then 

 refired to expel .any moisture gathered from the blos- 

 soms. Both black and green teas are thus scentel 

 into ihe varieties known as "Scented Caper" .ind 

 "Flowery Pekoe" which arc largely used in England 

 for mixing purposes. 



