The juices of various trees have been brought to notice as pbssible substitutes for gutta percha, but none of them have been found to answer, not even the sap of Euphorbia cattimandn from the Coromandel coast, which at one time was considered a likely substitute. The gutta percha from Borneo is not so much esMemed as that from the Malay Peninsula, and doubts exist as to the identity of the trees. It seems to be a practice with the people who collect the gutta perelia of the Malayan Peninsula, to mix the juices of several other species of Isonandra with that of the true Isonandra gutta. And though' this mixture confessedly depreciates the value of the gum, as the products of the several species have to some extent siinilar properties, the adulteration allows the commercial article to be applied to many purposes in the arts, from which the higher price and the scarcity of the true gum gutta would exclude it. There are said to be five or six species of Isonandra 011 tho Koondahs of the Western Ghats of India,—I. Wightiana, I. Perottetiana, I. Candolleana, and I. lanceolate ; and in Ceylon are I. grandis, and five other species. Some of these, however, have been referred to other genera, or are synonyms. One in the Peninsula, the I. acuminate, 1Vight, is now referred to the genus Bessie (B. ellipties), which yields the Pachonti, etc. General Cullen brought to notice the Pa chonti tree of .Malahar, but it was not found of much commercial value. The Dutch Government, while taking measures to transplant and cultivate the Isonandra gutta in Guiana, discovered at Surinani a juice-yielding tree possessed of analo gous properties in the Sapota Mulleri, believed to be the same as the bullet tree of the English. It is a tall tree, yielding in the hot season a large quantity of milky juice. The tree grows abundantly
on slightly elevated situations. The trunk is sur rounded with a ring of clay, with elevated edges, and then an incision is made in the bark as far as the liber ; the milky juice flows out immedi ately, and is collected in tho clay reservoir. The juice resembles in some respects the milk of the cow ; it forms a pellicle on its surface, which is renewed after removal. By the evapomtion of the juice, 13 to 14 parts in 100 of pure gutta percha is obtained. Six volumes of absolute alcohol, added to ten of the juice, separates at once all the gutta percha which it contains. Sulphuric ether acts more rapidly than alcohol. The juice is not coagulated by acetic acid. This Surinam gutta product is sold at Amsterdam at the same price as the best gutta percha of ecunmerce. The coagulated juice of a large climber found by Mr. Sandman, of Munnipur, in his grant, has been pronounced inferior, inasmuch as it is sticky, and becomes brittle when exposed to cold, and it would be unsaleable in England. A Cedar kind of gutta percha is also brittle, and when dissolved in chloroform or benzoic does not dry so quickly as the commercial article. On heating this in water it becomes most ductile and plastic, rather more so than common gutta percha. It is dissolved by the same agents as the latter.
Gutta of Borneo is collected in the Lewes district from at least five species of Isonandra, and adulterated with the juice of Ficus and one or two species of Artocarpen Gutta Podali of Billiton is vegetable wax.
Gutta Trap of Sing,apore is the inspisaated sap of au Artocarpus, used for birdlime.—Low's Sara wak ; Singapore Cat. London Ex., 1862; Indian Field, Calcutta, Juno 12, 1858 ; Tomlinson's Dic tionary; Burbidge,p.75. See Isonandm; Paehonti.