4©S 



THE TROFItCAL AaRICULTURiST. [Dec. i, i3?6. 



questions of food supply. These matters do not in- 

 validate anythinfj Raid above, hut they do profoundly 

 sfifect the problems of the diseases of plants, and 

 ( sptcially those dist-ases which start from the roots. 

 H. MAB.SHALL Ward, m. \., v. l. s. — Gardeners' 



Chronicle. 



^ 



TEA HAIR. 



Tea-makers will agree with us that hair, of 

 all substances in nature, is least likely and least 

 desirable as a component of the fragrant leaf. 

 But all Indian and Ceylon tea planters are familiar 

 with a substance, somewhat resembling the pollen of 

 flowers, which collects on the machinery in the pro- 

 cess of manufacture and which we have heard gener- 

 ally described as " orange " or "golden pekoe dust." 

 The general impression, we think, has been that the 

 dust in question was specially derived from and was 

 about the richest portion of the pekoe buds. Our 

 attention has, however, been attracted to a paper 

 in the "Year Book of Pharmacy for 1877," in 

 which it is shewn that the main constituents of 

 the substance, are hair-like processes which are 

 separated from the leaves in the act of rolling. 

 In taking over the extract we invite communi- 

 cations as to the proportion of this substance 

 formed in extensive manufacture ; whether it is 

 genera ly collected for exportation and what its 

 commercial value may be ? 



FUKTHER KESEAROHES ON TEA HAIR. 

 Bt Thomas Greenish, f.c.s. 



Under the name of Pekoe Flower, or Flower of 

 Tea, this substance was brought before the Conference 

 at Glasgow last year by Mr. Grcvef, and on that 

 occasion [ gave the result of its examination, maiuly 

 microscopical, which I had previously undertaken. At 

 that time but little was known either by Mr. Groves 

 or myself of its history, the position it occupied in 

 commerce, or its ultimate destination. I followed up 

 the subjfct with the view of supplying for this meeting 

 that more complete information which was wanting 

 ou these !^everal points, as the tea hair may probably 

 crop up again as a natural curiosity for a lover of 

 science, or to supply a sensational paragraph for a 

 public analyst. The tea h;dr was said to have'emauated 

 from a house in the city, but the city is a large 

 place in which to look for tea hair,and I found it so. 

 For many months I worried with my inquiries tea 

 brokers and tea merchants, but without result, until 

 at last a friendly hint directed me to a tea broker's 

 office, where I found a member of the firm who, in 

 adoi'ion to a very discriminating palate as regards 

 the strength and tiivour of tea, had also acquired a 

 vast deal of collateral information about teas imported 

 from India and China. 



It Bppears that tea hair finds its way into tbia 

 country as an article of legitimate commerce, at 

 tolerably regular intervals; its commercial name is 

 "Pekoe Flower," and soQietimes the "Bloom of the 

 Pekoe Flower." It is a product of India teas, not 

 of those of China. It is purchased somewhat as a 

 curiosity, but there arc those who buy it pretty 

 regularly. Pekoe flower is never sold as tea simple 

 or for mixing with tea. It is almost a necessity 

 that it should be sold alone. If it be mixed with ordinary 

 tea there is such a tendency to the sopa'-ation of 

 the tea hair and its agglomerition into lumps, that 

 any attempt of this kind would probably result in 

 the whole being returned as an adulterated tea. 



In an essay on the cultivation and manufacture of 

 Indian teas by Lieut. -Col. Mo?iey, and published in 

 Calcutta, the whole process of the manufacture of 

 the Indian ttas is givtu, and it is not <lilticult to 

 trace the condition in which this tea hair is found, 

 to its origin. One part of the process consists in 



what is called " rolling " the leares, when the juice 

 is given out freely; and as to its results ou the leaf, 

 ho says, ''If the leaves which give Pekoe tips aie 

 separated from the other leaves and rolled vtry little 

 and very lightly there will come out Pekoe tijjs of 

 a whitish colour ; if not hcparated from the other 

 leaves, but manufactured with them, the sap from 

 the other leaves, expressed in the rolling, .stains these 

 said leaves, which are coverid with a tiiK-- silk}- down, 

 and makes them look like the rest of the tea.'' This 

 is evidently the part of the process in the manufacture 

 of Indian teas which gives to the otherwi.^e grejish- 

 white hair its brown colour, and also that extractive 

 matter which is found adhering to it. 



Mr. Wiguer, in his analysis of the tea hair, gives 

 theine 1"5 per cent as compared with 80 per cent 

 for Pekoe tea, and Mr. Groves remarks in reference 

 to this, that "it is interesting to find theine present 

 in the tea hair." 1 doubttd the correctness of this 

 conclusion. The hair of the leaf is an extension of 

 the epidermal cells covered by the cuticle ; there is 

 an absence of chlorophyll, the cells being empty ; 

 this layer prevents too rapid evaporation from the 

 parenchyma of the leaf, but plays no part in the 

 plant's economy. I have no doubt but that the 

 theine obtained by Mr. Wiguer was derived from 

 extractive and parenchymatous tissue adherent to the 

 base of some of the hairs. To determine this point, 

 I took 100 grs. of tea hair, exhausted it with cohl 

 water and evaporated the liquid to dryness. It 

 yielded 15 grs. of extract; this closely agrees with 

 the result obtained by IMr. Wigner. My ol)ject was 

 now qualitative, to determine tlie presence of theine 

 in the extract, and for this 1 adopted the micro- 

 sublimation process. A little of the extract was 

 dissolved in water, to which was a ided some Cilcined 

 magnesia ; the solution was boiled and evaporated to 

 dryness; part of it was then placed in a cell on one 

 glass slide covered by 'another, and at a temperature 

 of about 120 -' 0. I obtainel successive crops of theine 

 in acicular crystals. I then subjected the hair from 

 which the extract had been obtained to the same 

 process, but there was no indication iu the hair freed 

 from extractive of the presence of theine. It is evident 

 that this experiment on the exhausted hair could 

 not be considered conclusive as to the absence of 

 theine in the normal hair of the tea leaf. I further 

 picked carefully clean hairs from young Pekoe leaves, 

 treated them iu the same manner by gently boiling 

 with a little calciued magnesia, and emplovcl the 

 same micro-sublimation process, but failed to get the 

 slightest indication of the preseucj of theine iu the 

 hair itself when free from extractive matter and 

 parenchymatous tissue. These experiments are to my 

 mind conclusive that the theine was obtained from 

 the extractive matter and parenchyma of the plant, 

 and that there exists no theine in the normal hair 

 of the tea leaf, and I believe that there is no known 

 instance of a simple hair, such as that on the tea 

 leaf, containing ttie active principle of the plant. A 

 further careful e.xaraiaation of the tea hair, besides 

 calcareous matter, shows the presence of minute 

 panicles of the elytra of beetles, the marking."? on 

 which bear a cl '»e resemblance to the venation of 

 a, leaf, and which ni:»y easily be mistaken for frag- 

 raeiits of NOine leaf other tbau tea, i may aid that 

 the tea hair has created considerable interest, and 

 I aire been applied to frojM the continent for 

 museum samples, which until lately I was quite 

 unable to supply, 



Thinks havmg been voted to Mr. Greenish for his 

 paper. 



Mr. Groves said he could have saved Mr. Greenish 

 a great deal of trouble if he hafl known that he 

 was in search of the importers of the tea hair. 

 It was no mystery — he had known all about it from 

 the first. The general impression was that this tea 

 hair was worked up into the compressed te^, as the 

 only way of getting rid of it. As to the presence of 

 theiu", the presumption was in favo'ir (jf Mr. 

 Greeui>h's theory that it was tiot- preseut. — Vcitr Hook 

 of rharmacy ani Transact ions of the lU-itish PharvM' 

 ceutical Conference for 28/7. 



