AND OF THE PHYSICAL SCIENCES. 



15 



became unruly, but the former silence was soon restored. The Vultures 

 did not immediately attack the dead animal ; they drew their neck from 

 the ruff, and remained ogling it for some time. " Tern be the judghes, 

 and tern sit in court now to hold judshement o'er em," observed the Ne- 

 groes who were standing around us; and the remark was so adapted and 

 striking that we could not help smiling at it. After half an hour had 

 elapsed one of the male Vultures commenced the entertainment, and his 

 example was soon followed by the others. Towards evening the Vultures 

 had satisfied their appetite, and the Carrion Crows commenced their feast ; 

 where harmony, however, did not appear to be presiding, and scuffles and 

 quarrels took place when it concerned a favourite morsel. 



These beautiful birds soar uncommonly high, and possess great powers 

 of flight. Like the Eagles they hover over one and the same spot for a length 

 of time, poise their wings, and please themselves in aerial evolutions, un- 

 til their sharp scent and sight combine to show them the direction where 

 their appetite may be satisfied, when they descend in gyratory motions. 

 They do not decline animal food of any description, provided it does not 

 possess life, as they are not known to kill. They are cowardly birds, 

 and do not oppose, in single combat, one animal which offers resistance: 

 They rise with heavy wings and a great noise. 1 have not been able to 

 ascertain where they build their nests ; very likely in the most retired 

 places. The young males are in their first year black ; they become 

 black and white spotted during the second, and are only in full plumage 

 during the third year. They are easily tamed if taken young. Mr Glen 

 in Demerara had a female bird, which was so tame that it would lay 

 itself before its master's feet. I saw a full-grown male bird which was 

 brought from Surinam to Demerara ; it was perfectly tame, and was ul- 

 timately sold to the master of an English merchantman for the enormous 

 price of twenty pounds {Annals of Natural History fur December 183S.) 



On the Nature of Stonge.— A series of papers have lately been read 

 to the Linnaean and Royal Societies, by John Hogg, Esq., upon the 

 Spongilla jiuviatilis, to which we would more earnestly invite attention, 

 as it must be known to many of our readers that Naturalists are not 

 agreed as to the true nature and history of Sponge; some supposing it 

 belongs to the animal kingdom, and others to the vegetable. These op- 

 posite conclusions are the result not of mere theories, but of the most 

 careful microscopic observation, demonstrating the great difficulty of the 

 subject, and the still remaining imperfections of science, which, however, 

 are the less to be regretted as they stimulate the lover of truth to renewed 

 investigation. Mr Hcgg is an advocate for the vegetable nature of River 

 Sponge, and he supplies additional observations in confirmation of his 

 views, derived from a more accurate observation of the seed-like bodies, 

 which are found adhering to the walls of the cells or cavities of the 

 Sponge, and also frequently free, and endowed with the faculty of loco- 

 motion ; and which have been regarded by some authors as the Ova of 

 Spongilla, and by others as those of the Plumatella. Mr Hogg has de- 

 termined the identity of these bodies, having succeeded in raising young 

 Spongilla from both kinds ; and he has also ascertained that they are 

 destitute of cilia, being merely studded with minute granular papilla?. The 

 motions of the unattached bodies resemble those observed by Unger in 

 the Sporules of Ectospora Clavata, and Mr Hogg considers the currents 

 to be due to the same causes which affect the circulation of the fluids in 

 the cells of vegetables. 



Megatherium. — In a memoir presented to the French Academy of 

 Sciences, M. de Blainville states, that neither the head, the shoulder, 

 the limbs, the feet, nor the dentition of the Megatherium, in any manner 

 resembles those of the Sloth, to which tribe the late Baron Cuvier re- 

 ferred this gigantic animal. M. de Blainville places it among the Arma- 

 dilloes, where he conceives it ought to form a particular division, because 

 it probably had four toes in front, and five behind ; and the teeth are 

 not only tetragonal, contrary to those of the Armadillo tribe, but there are 

 only four in each jaw, which is also an anomaly. 



BOTANY. 



Caoutchouc or Indian Rubber The increasingly important sub- 

 stance Caoutchouc is a widely dissiminated constituent of vegetable fluids. 

 It has hitherto been found only in plants with milky juice, although its 

 presence in all these fluids remains to be proved. The presence of 

 Caoutchouc in silk has been attributed to the nature of the fluids of the 

 plants on which the caterpillars feed ; but this, though applicable to 

 the mulberry plants, can scarcely hold good with the various species of 

 Tetranthera, on which the Moonga feeds, or with the Castor-oil plant, 

 the chief food of the Eria, which in Assam does not appear to yield milk. 

 Milky juice is usually characteristic of certain families, but often not ; 

 its presence is frequently of importance, as it affords valuable indica- 

 tions of affinity. It is remarkable that it is almost unknown in the grand 

 division of Monocotyledonous plants. The families in which its presence 



may be said to be universal are Apocquea, Asclepiadea, Campanulacea, 

 Sobeliacea, and the great division of Composite, Chicoracea, of which the 

 lettuce is a familiar example. It is of common occurrence in Euphorbiacea, 

 and Tulicea, which orders may be looked upon as the grand sources of 

 Caoutchouc. Thus, in addition to the East Indian plants, the American 

 Caoutchouc is supposed to be produced by Cccropia-pcltata, which be- 

 longs to Urticea; and the ule tree of Papantla, from which the Caout- 

 chouc of that country is obtained, is supposed to belong to the same 

 orders. It must, however, be observed that Baron Humboldt objects to 

 the supposition of Cecropia peltata yielding the American Caoutchouc, 

 as its juice inspissates with difficulty. The order Euphorbiacea would 

 likewise appear to supply a large quantity. Dr Lindley informs us that 

 true Caoutchouc is furnished by Siphonia elastica, Hevia quiancusis of 

 Aublet, a Surinam and Brazilian tree ; and it is from a tree of this order 

 that asubstance resembling Caoutchouc is procured in Sierra Leone. Some 

 Apoquece are also reported to produce good Caoutchouc ; thus Aricula 

 elastica, produces the Caoutchouc of Sumatra ; and it is from this plant 

 that Caoutchouc has been produced in Penang and exported to England. 

 Roxburgh says that that produced from Willughbeia cdulis, an Indian 

 plant, is of indifferent quality, a criticism which will not be passed on 

 that obtained from Nerium grandifloreum of Roxburgh. It is probablv 

 equally abundant in Asclepiadea ; one plant of which order, Cynanchum 

 atbifloreum, has been stated to yield it ofexcellant quality in Penang. 



Caoutchouc, we need scarcely add, is that substance now so much 

 employed in the manufacture of waterproof cloths, and of tubes, cylin- 

 ders, &c. most useful in the arts. It owes much of its value to its being 

 insoluble in water, spirits, acids, alkalis, and in most liquids ; its ap- 

 propriate solvents are Ether, which, however, requires to be free from 

 all admixture, and volatile oils, the cheapest of which is the volatile oil of 

 Coal-tar, now known by the name of jVii/)/i(/i». When pure, in its native 

 state, it is white; and becomes of a brownish and blackish colour from 

 the juice, which is generally collected in a mould, being subsequently 

 dried in the sun's rays, and then exposed to smoke; successive layers 

 being put on till it is of the requisite thickness. In all the different 

 methods of collecting it the extraneous soluble matters contained in the 

 sap are apt to he mixed up with the Caoutchouc, and continue incorpor- 

 ated with it when solidified ; hence, its strength and solidity, and, of 

 course, its value, are considerably diminished. In some kinds these im- 

 purities are more considerable than in others, and the imperfect adhe- 

 sion between the layers which compose the Indian-rubber bottles are 

 attributable to a very thin layer of these impurities. Mr E. Solly lately 

 read a paper on these points to the Asiatic Society, detailing experiments 

 he himself had made, and considering how far improvements could be 

 effected in its preparation. — (See Journal of the Asiatic Society of Bengal, 

 Mr Griffith's Report; Dr Lindley's Works on Botany, fyc.) 



The Tea Plant The vast economic and commercial importance of 



Tea, and the combined selfishness and arrogance which pervades the 

 Celestial Empire, upon which we have hitherto been dependent for the 

 supply of that necessary commodity, confers the highest interest upon 

 every effort which is being made for the more extended cultivation of this 

 invaluable plant. In the year 1812 it was first introduced into the Bra- 

 zils. Its success there has been very promising, and more especially 

 since 1825 the progress made has been rapid, so that the growers are 

 already able to supply a large portion of the Tea required for the home 

 market. It is extensively cultivated in Ouro-Preto, and in the province 

 of St Paul; is extending into the province of Minas, and has been at- 

 tempted on a large scale in the Botanic Garden at Rio de Janeiro. At 

 a much more recent date the Tea plant having been observed to he in- 

 digenous in Assam, that province of our Eastern empire which on the 

 north-east most approximates to China, public attention was excited to 

 its careful cultivation and manufacture. An experimental company has 

 been formed for the furtherance of this object, which has obtained the 

 encouragement of the Directors in Leaden hall Street, of the Board of 

 Control, together with the approbation of the Board of Trade. It was 

 through the agency of these bodies, that the chests already received in 

 this country, samples of which afforded such peculiar satisfaction, have 

 been widely distributed throughout the kingdom. Our active and intel- 

 ligent neighbours, the French, seem determined not to be behind hand in 

 deriving benefit from this source. Not many months ago the French go- 

 vernment despatched M. Guillemin, one of the Curators of the Jard/n des 

 Plants, to the Brazils, for the purpose of studying the culture of the Tea 

 plant, the methods of preparing the Tea for market, and of collecting 

 seeds and plants, that an attempt may he made to introduce its culture 

 into France. M. Guillemin arrived at Rio in October last, and has been 

 most kindly received by the authorities and naturalists of Brazil, who have 

 shown every inclination to promote his wishes. M. G., after examining 

 into all the details, is sanguine in his hopes of success ; and the mere at- 

 tempt, made in our day, to introduce both Tea and Sugar as home-grown 



