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their sides and the interstices filled with a black ferruginous substance sometimes dull and sometimes shining (apparently hydrated oxide of iron) and of quartz holding a similar substance in seams also occur. One of the largest and boldest cliffs has been converted into a compact siliceous rock pervaded by numerous quartzose and ferruginous dykes and veins. In some places a complete net-work of fissures ramifies through the rock, and it is evident that quartzo-ferruginous gas or vapour has been injected through these fissures and the large veins and dykes, and metamorphosed the rock.
At the Water Islands south of Malacca, and at Tanjong Panchur and Budewa to the north, I carefully examined some large developments of granitic rocks. In the former I found some dykes composed of quartz felspar and a ferruginous substance similar to that already noticed. In decomposed felspar and also in solid quartz in those dykes I found much both of decomposed and of undecomposed iron pyrites. Although these dykes seem to countenance the idea that the plutonic agency which has so greatly affected the superior rocks was exerted after the formation of the upper granite, I have from all my observations come to a different conclusion. I cannot now state its grounds, and I do not positively bind myself to an opinion to which perhaps I cannot demonstrate beyond doubt to be correct, but the result of my constant consideration of the subject in all its relations, and with reference to every new locality that I have explored, is as follows:– The whole region has been subjected to plutonic reduction. The plutonic fluid by its pressure has caused fractures in N. W. S. E. lines, and it has swollen up in ramifying bands having that general direction. Its pressure and heat have varied at different portions of its surface. In some places the heat has been so intense as to reduce all the superincumbent rock up to the very surface into its own substance, and it has swollen up into mountains in the interior and hills in the exterior lateritic tracts of the Peninsula.”
* This is opposed to prevalent theory, and it may be asked whether in that case it would not have flowed over ? But I have found it impossible to apply the prevalent plutonic theory, I mean that of a necessarily Tartarean origin of granite, &c., to the granites of the south of the Peninsula, considered even per-se, and I would ask in return whether there is any proof or probability that granite prior to solidification ever exists in the upper crust of the globe in any other form than as a viscid cohesive mass. Let Fig. 1, Pl. XXII. be the surface of a plutonic bubble swelling up and reducing The transformed and partially transformed sedimentary hill ranges rest, I conceive, upon granitic bubbles* where the plutonic action has been less intense. The fissures and cracks formed by the pressure of these bubbles have been the channels, the gases given off from their surface the immediate agents, of all the alterations. The tracts where only granite now appears swelling above the surface had previously passed through the same stages. In other words laterite is one of the earliest stages in the reduction of the upper rocks superincumbent on a plutonic sea into the substance of which that sea is composed. Where the heat has been least intense, the upper rocks have merely been raised,—where greater, lateritic, scoreous, and other partially altered, hill ranges, have been produced. A higher degree of plutonic action has produced quartzo-ferruginous ranges like that of Cape Rachado. The highest degree has transformed or reduced the whole into granite and allied crystalline rocks, from the mode in which the granites, &c. come to the surface at Singapore, we see that the whole region there has been broken up by the plutonic sea below. I can proceed no further however at present, and must close this rough draught of my ideas.
the superincumbent rock as well as upraising and fracturing it. A great fissure would probably be produced when it reached a certain nearness to the surface. As it slowly pressed up it would appear as in (fig. 2), but as it became exposed to the atmosphere, it would have an increased tendency to solidify at the surface, and as it rose above the level of a d, (fig. 3), it might already have a semi-solid shell sufficient to prevent the already thickening mass within from swelling out laterally over the surfaces ab, ca : but suppose it was sufficiently viscid to do so, the consequence would be that the spaces o o (fig. 4), would be exposed to an intense heat on two sides and be reduced in a more or less crystalline form to a portion of the bubble. I believe that granitic bubbles always swell up with exceeding slowness, and that the centre of the bubble (if its base be of great size) may remain for centuries, or even longer, in a viscid state, while a thick solid crust of granite has formed on the sides and summit, and that the central part will still exert as slow upward and outward pressure as it solidifies. and may itself be subject to a long continued elevatory pressure from the sea belowIn other words the summits of granitic mountains and minor masses may go on rising above the base, after the latter with the whole surface has solidified, and when the base has no further upraisd movement save what it may possess in common with the plutonic sea below. Great dislocations in the upper crust must necessarily result, but does not every plutonic mountain range bear witness to such dislocations ! I must refer to my paper on Púlo U'bin for the facts on which these veins are based.
* I do not mean that each base or hill range has a corresponding protuberance on the surface of the plutonic base, but that the whole system of hills and hillocks has been produced by unequalities in that surface and by the directions which the principal and divergent lines of fracture have taken.
On Parious Genera of the Ituminants, by B. H. Hongsos, Esq., Dorjeeling.
That there are more false facts than false theories in science is the profound remark of an eminent philosopher, and a remark which it is peculiarly incumbent on the real student of Nature heedfully to bear in mind in relation to Mammals, because genuine wild specimens exhibiting the mature and characteristic marks of their species are to be had but rarely and accidentally (owing to the progress of cultivation in all but utterly savage lands); whence has resulted almost necessarily a host of descriptions which, being drawn from very imperfect materials, are inadequate to fix the species, and a host of generalizations which, being deduced from such descriptions, are, of course, imperfect as generic designations.
Such imperfect descriptions of species, and consequent defective (by omission and error) designations of them when thrown into classes or groups, are to be found in works of the highest authority; and, though the causes of these short comings are obvious and not wholly matter* of reproach to our eminent guides in Zoology, yet is it very desirable now and then to caution the ordinary observer against them, lest implicit reliance upon high authority should cause his attention to slumber or somnambulize when it is of the utmost importance that that attention should be wide awake and directed towards all the points to be observed; for, the phoenomena being as scattered as they are numerous, and capable of being adequately noted only at the time and place of their rare and lucky occurrence, it is the one thing needful to the sound progress of the science whose business is with such phoenomena (the structures and the habits of wild animals) that alert observers should exist every where, in order that the rare occasions of observation
be not lost.
* Not so in so far as the phoenomena are casual, rare, and eminently dependant on time and place and lucky accident for means of adequate observation—but really so in so far as these persons have taken no measures whatever to enable those whose positions are favourable to the observation of such phoenomena to make the right use of their unique opportunities. This is the opprobrium of Zoological Societies, and a most grave one it is, though one from which many of the most eminent writers on Zoology are free, as having nothing to do with Societies,
I am fusly of Cuvier's opinion that we are now 100 years too soon for the possible tracing of the filum areadneum of Nature, and consequently that the dry skin and inference system of the closet—which ambitiously seeks to work out an impossible problem by means the most inadequate and unfit, instead of supplying guidance to the only persons who are in a position to complete the necessary preliminary observations of the phoenomena thus prematurely sought to be generalized—is a mistake and a grievous one. But, though I hold that all present attempts at a general Systema Naturae are folly, and that the true business of the master of Library and Museum in the present infantine state of the science is, to quicken and guide the observing powers of the field maturalist and to thus multiply infinitely the chances of effective observation of phoenomena which are necessarily as scattered in the place, as uncertain in the time of their occurrence, yet have I no intention to underrate the value of subordinate Zoological aggregations or classings of animals into minor groups or genera, in the light of helps to memory and guides to observation.* On the contrary, I am most fully aware of the importance of all such classifications in this light, and especially with reference to the material end of quickening and directing ordinary observation ; and what I regret is that no pains are bestowed in the proper quarter to draw up and disseminate any such directions, Let such a ‘how to observe' be framed for each country where observation is still needful; let it exhibit side by side the popular and scientific names of the chief groups of animals in such country; and let each group have appended to it a distinct enumeration of the actual or supposed essential characters of such group, in other words, of the points that ought to be observed in regard to each group, whether for verification or augmentation; and in ten years Zoology will make more real progress than under the continuance of the present system it can do in a century !
The characters of the several groups of animals proper to any given country are now only to be had peicemeal in numerous costly works wherein hardly any one has time or means to seek them; and they exist there, moreover, overlaid with a deal of the leather and prunella of cumbersome useless lore. Let the characters of groups be brought together in a cheap form, and stript of their buckram, and numberless men of sense and education will be found ready to apply them to their only true use in the examination of such wild animals as chance may throw into their way, though such men may be slow, as heretofore, to toil blindly for the convenience of others who ought to, but do not, seek to give interest and effect to their independant researches. Such a guide to ordinary observation is the one thing needful in order to interest men of sense in the matter. Let the means and ends, the structure and the habit, the organ and its use, be thus juxtaposed, and intelligent curiosity will soon be generally turned towards this wonderful system of adaptations, emanating from omniscience. Nor does it materially signify that all the indications of a genus or group of animals be accurate. Only let all of them be set down, some in the shape of queries, and observation under favourable circumstances, that is of the fresh and perfect animal, not of its mere skin, will soon determine the fitness or reality of all such negative or positive marks of a group of animals as are supposed to belong to it. Structures and manners are the two heads under which the directions I advert to should fall. Let the ‘what to observe' upon each of these two points be separately set down and applied to the several distinct lots or assortments of animals proper to the country, and there will be forthwith a general and unlooked for effort to fill up the Zoological desiderata! I pretend not in the present paper fully to exemplify my own precepts as above given; nor have I the appliances requisite to the performance of the entire work suggested. That work must emanate from the public Museum and Library, and ought long since to have emanated from them, as their appropriate and best (infinitely best) fruit and repayment of the general contribution. For, where the phoenomena to be ascertained are those of rare and secluded animals, where the real objects of study are vital organs and their uses, let me ask any man of sense if there be any limit to the superiority of a system which should qualify the only persons in situations to note such phoenomena over the system which practically leaves such a work wholly to half a dozen men shut up in cities, though they are obliged to perform it by means so inadequate as skins, eked out now and then by bones 2 This is a question well worthy of the consideration of Zoological Societies. My present purpose is to add my mite in the way of popularizing and A U.
* Such guides will always tend more and more towards the natural system, and the best will still be those which least conflict with it.