July i, 1882.] 



THE TROPICAL AGRICULTURIST. 



or cocoa-nut oil. If oue pint of lime juice, be added 

 to three gallons of gutta juice, the latter coiigulates 

 immediately on ebullition. 



On arriving at the port of shipment the gutta before, 

 exportation, generally undergoes examination and 

 classification into parcels, according to quality. As 

 received in the "godowus"or warehouses it presentes 

 great diversities in condition, shape, size, and eolonr, 

 — from crumbling, hardly coherent, whitish or greyish 

 "raw" or " getah muntah" fragments, to reddish or 

 brownish blocks as hard as wood. Sometimes it is 

 made up into all manner of grotesque shapes of 

 animals, and it is nearly always largely adulterated 

 with sago-flocir, sawdust, chiy, stones, &c. The Chinese 

 are great adepts in assorting and classifying gutta. 

 and frequently prepare from different varieties a 

 certain "standard sample" by cutting or chopping 

 the material into thin slices and boihng with water 

 in large shallow iron pans, keeping the contents con- 

 stantly stirred with polfs, and adding good gutta 

 percha and even cocoa-nut oil to give a better apiiear- 

 ance. When sufficiently boiled the gutta is pressed 

 into large moulds, and is then ready for shipment. 

 This process of reboiling is wholly unnecessary, and 

 in some cases is done only to get rid of stuff which has 

 no right to be called "gutta percha." 



The amount and value of gutta percha imported 

 into Great Britain in 1875 77 were as follows: — 

 1875. 1876. 1877. 



Cwts 19,686 21,558 26,359 



Value £149,684 £163,441 £2.38,327 



The price of gutta percha ranges from 4d. to 3s. 

 per lb , according to quality and demand. 



History. — The early history of the use of gutta percha 

 is somewhat obscure ; the Malays and Chinese are 

 said to have long known and used it. One of tlie 

 earliest notices of it in England occurs in a catalogue 

 of the collection of the famous Tradescants.* Dr. 

 Montgomerie, a surgeon in the East India Conqjanv's 

 ser\'ice, was the first to direct attention to gutta 

 percha as likely to prove of great utdity in the arts 

 and manufactures. Having observed the substance 

 in Singapore in 1822 in the form of whips, he com- 

 menced experimenting with it. lu 1842, being again 

 stationed at Singapore, he followed up the subject, 

 and his recommendation of it to the medical board 

 of Calcutta as useful for making of splints and other 

 surgical appai-atus met with high approval. He also 

 sent specimens, with relative information, to the Society 

 of Alts of Loudon, which society warmly took up 

 the suliject, and on Montgomerie's return to England 

 in 1844 preseeted him with its gold medal. Some have 

 claimed the honour of introducing gutta percha to 

 the notice of the commercial world for I )r. (after- 

 wards Sir) JosiS D'Almeida, who sent a specimen merely 

 as a curiosity to the R0y.1l Asiatic Society in 184.5, 

 but careful investigation clearly decides the question 

 of priority in favour ot Montgomerie. The Society of 

 Arts havin:; requested him to lay before them the 

 result of his experiments, he delivered a lecture in 



* In the Mmeum T radescant ianum ; or, a Collection 

 of liarilies iirtherved at south Lambeth, near London, 

 by John Tradescant, . . . Loudon, mdclvi., the 

 ■ foUmving entry occurs (p. 44) :— " VIII, Variety of 

 Earities. — The plyalile mazer wood, being warmed, 

 will work to any form." This museum became the 

 nucleus of the Afhmolean Museum at Oxibrd. The 

 word ''mazer," variously spelt, often occurs in early 

 English poetry, and is sjjecially mentioned in old 

 catalogues and wills. It is by no means impossible 

 that mazer cups may have been inaf'e of guttapercha, 

 as its lightness, strength, and non-liability to fi-ai^tme 

 would recommend it ; and curiously enougii one of 

 the vernacular names of the tree yielding gutta percha 

 is "mazer wood tree." 



the autumn of 1844, and many patents were at once 

 taken out, the chief being those of Mr. C. Hancock, 

 Mr. Nickels, Mr. Keene, Messrs. Barlow and Forster, 

 Mr. E. W. Siemens, and other. After this the sub- 

 stance soon came into general use. * 



Properties. — Gutta percha, like many other milky 

 juices, occurs in the lactiferous tissue of the plant, 

 which exists in greatest abundance in the middle 

 layer of the bark. See Bot.\ny, vol. iv. p. 87. 



Gutta percha is resolvable into two resins, albin 

 and fliiavil. Like caoutchouc or india rubber, it is 

 a hydrocarbon ; Soubeiran gives its composition as 

 — carbon 87'80 and hydrogen 12 20. In commercial 

 gutta percha we have this hydrocarbon or pure gutta, 

 plus a soft rCbin, a resultant of oxidation of the 

 hydi'ocarljon. M. Payen gives the following analysis 

 of commercial gutta percha : — 



Pure gutta (milk-Hhite in colour and fusible), 75 

 to 82 per cent. 



Resins soluble in boiling alcohol ; — 



1. Crystalbin or albin {C,,oHj„0„), white, and 

 crystallizing out of the alcohol as it cools, 6 to 14 



per cent. 



2. Fluavil C^„H320), yellow, falling as an amor- 

 phous powder on the cooling of the alcohol, 6 to 14 

 per cent. 



It is thus apparent that the change of pure gutta 

 into a resin-like mass takes place naturally if means 

 be not taken to stop it. Many a good parcel has been 

 thus lost to commerce, and the only remedy seems 

 to be thorough boiling as soon after collecting as 

 possible. It must be remembered too that, in outtino- 

 through the bark to arrive at the laticiferous vessels, 

 many other vessels and cells become ruptured, con- 

 taining tannic and gallic acids, &c., and the jjresence 

 of these no doubt accelerates oxidation. In openin" 

 bottles of the milky juice a turbidity and effervescence 

 are often noticed, owing to the formation of a brownish 

 liquid, the colour being probably due to the presence 

 of gallic acid. In improperly prepared blocks of gutta 

 also, these foreign substances induce the presence of 

 a brown fermented and putrid liquid which decomposes 

 the internal mass. Many of these .substances, being 

 soluble in water, are removable by the process of 

 boiling. 



Gutta percha as met with in commerce is of a 

 reddish or yellowish hue, but when quite pure is 

 of a greyish-white colour. In this state it is nearly 

 as hard «s wood, only just receiving the impression 

 of the nail, is of a porous structure, and when viewed 

 under the microscope has tlie appearence of a series 

 of variously hued prisms. Wheu moulded, rolled into 

 sheets, or drawn into ropes, it assumes a fibrous 

 character in the direction of its greate?t length, in 

 which direction consequently it cau be stretched with- 

 out rupture. If however, a strip of a sheet be cut 

 oif across the fibre, it will be found that a redis- 

 tribution of the tenacitv of the slip takes place ; i. k. 

 the direction of the fibrou.s character is developed in 

 an opposite direction. The ehctricsl properties of gutta 

 peri;lui were first noticed by Faraday. If a piece be 

 subjected to friction, an electric spark can be obtained. 

 On its relative electric conductivity, see vol. viii p. 53. 



/ t a temperature of 32° to 77° Fahr., gutta percha 

 has .as much tenacity as thick leather, though inelastic 

 and less flexible. In water at 110° Fahr. it becomes 

 less hard ; towards 120° Fah. it becomes doughy, 

 though still tough; and at from 145° to 150° it grows 

 soft and pliable, allowing readily of being rolled and 

 moulded. lo this state it has all the elasticity of 



* See Collins on "Gutta Percha" iu British 

 Mannfacturing Industries (Stnnford & Co.), and the 

 very interesting volume of A/x ijications of Patents in 

 Caoutchouc, Outta Percha, &c., issued by thej Patent 

 Office. 



