frontier of China, upwards of 200 British miles. In this space, M. D'Anville, in his Chinese Atlas, lays down the sources of two rivers proceeding south into the territories of the Shan. The eastern of these I agree with Mr Dalrymple in considering as the Mækhoup river of the accompanying maps, which, in several authorities, is called Menantay (see this Journal, vol. ii. p. 269, 270); of course, it is a branch of the Mækhaun. The western of M. D'Anville's rivers I consider as a source of the river of Siam. Now, in the general map of the slave, this is said to rise with two heads, the Mæghuæ and the Mæpræn, the latter of which, after the junction, retains the name. But the river laid

down by M. D'Anville is so near the Loukiang or Saluæn, being only about forty geographical miles distant, that it is in all probability the Mæguæ. The Mæpræn, although reckoned the chief river by the Mranmas, must therefore either have escaped the notice of the Missionaries who surveyed the province of Yunnan, or its source must be without the limits which they chose to assign to the Chinese empire. There is, however, plenty of room for a considerable river being interposed between the two laid down by M. D'Anville; as, where they leave China, they are about 120 geographical miles distant. The intervening country, being occupied by rude independent tribes, may very likely have prevented the Missionaries from reaching this branch of the river; for, if it rose on the frontier, its course, in a direct line to Zænmæ, would only be about 180 geographical miles, while the course of the western branch would be 240 miles. It is not, however, always that the longest branch of a river gives the name; for instance, the Mississipi has not run half so far as the Missouri, when the latter, on joining it, is considered as lost. The Maghuæ probably joins the Mæpræn in about 20° 40′ N., and about half way between the junction and Zænmæ, the Mæpræn, which is a great river (Mrit) receives from the west the Mæle, which, although of considerable length, is only dignified with the appellation Khiaun, and would appear to have its source near the boundary of Upper Laos, unless we suppose it to be the same with the Mrænlo, which runs through the western parts of that country.

As I make the Mæpræn approach nearer the Mækhaun than Mr Arrowsmith does, it is necessary for me to consider, that the

small rivers rising.between these great channels should have a more oblique course than has been given in the map of Asia (Arrowsmith's), which copies too nearly the rude materials furnished by the slave. The course, of the Anan also, for the same reason, must be half a degree shorter than in this map. I am also of opinion, that the Main Zin, which in the map of Asia is made to come from the frontier of Upper Laos, has a much shorter course. Both maps of the slave place its source in a mountain between Tamat and Paboun, about half way between Zænmæ and that frontier.

The most essential difference between these maps, and the general one compiled by the same person, is, that, in the former, M. Gain, a military station of importance, is placed on the east side of the Mækhaun, while, in the general map, both it and Kiain Sin, another great military station, is placed between the Mækhaun and Mækhoup. I am inclined to think, that the first assigned situation for M. Gain is most likely to be true, not only because two out of three authorities are in its favour, but because the general map, being on a very small scale, the compiler probably bestowed less pains on the detail. As, in 1795, the country between the Mækhoup and Makhaun was certainly under the government of the chief residing at Kiainsin (Kyanseng of the Universal History; see this Journal, vol. ii. p. 270), and together with M. Læh, M. Koup, and M. Sæn, on the frontier of China, formed at one time part of Upper Laos; so it is probable, that M. Gain, and the towns on the east side of the Mækhaun, formed the province of Kemarat of the Universal History. This also, in 1795, was governed by its own great military officer; but at times has also been, no doubt, subject to Upper Laos. It extends from the frontier of China in about Lat. 22° to about Lat. 20o, and is probably thirty geographical miles wide. In these maps, therefore, the Slave has not only included the country of the Jun Shan, but a great proportion. of Upper Laos, that, in 1795, had been indeed separated from the prince of that country; but had not been given, entirely at least, to the prince of Zænmæ; for it is not unlikely that the towns laid down in the northern parts of the first map, but which are not mentioned in the second, may have at one time VOL. X. NO. 19. JAN. 1824.

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belonged to Upper Laos; at any rate, they would not appear to be under the government of the two military chiefs.

The whole territory included in the first map extends, along the parallel of 100° E. from Greenwich, from the boundary of Siam to that of China, about 200 geographical miles; and along the 20th degree of N. latitude about 200 geographical miles; and, being nearly of a quadrangular form, it will contain at least 46,000 square British miles, after making every allowance for its diminishing in length somewhat both on the Saluæn and Mækhaun. If we allow 16,000 miles of this extent to have belonged to Upper Laos, we shall still have an extent for the principality of the Jun Shan greater than that of Scotland. Its prince, it was acknowledged, was merely tributary to the king of Ava, and among his own subjects was called a King (Pua), although the pride of the Amarapura courtiers only honoured him with the title of Zabua; but he was not called upon to attend that insolent court, when the ordinary tributaries of the Shan race (Żabuas) made their annual homage in presence of the English embassy.

The capital city, called Zænmæ by the Mranmas, in the vulgar dialect of the Siamese is called Zima; but its natives more commonly call it Sunabuni (built of gold), as the Mranmas usually call their capital by the magnificent title Shue Prido (golden abode of royalty). In the sacred language of these nations the name of this city is Harimunza, just as Amarapura is the sacred name of New Ava (Ænwazit). So far as I can conjecture, after weighing all accounts, it is situate in a few minutes more than 20° of N. latitude, and in a few minutes less than 100° of longitude East from Greenwich, in a situation very advantageous both for fertility and commerce, the Mæpræn being navigable to the sea, and having through the Anan a navigable communication with the great river Mækhaun. The dialect spoken by the natives of this country, which I saw at Ava, could not be distinguished by me from that of the Siammese, every word that I asked appearing exactly the same; but the accent appeared very different to the natives, although of this I was not sensible. Both nations seem also to be nearly in a similar state of society, and progress of arts.

The distances, denoted by Roman numerals in the second map, are days' journeys; those denoted by cyphers are leagues of Ava. Both in the maps and account I have used the contraction M. for Muin or Hmain, the Siammese name for a city.

ART. X.-Observations on M. Beudant's Opinions regarding the Crystalline Rocks of the Red Sandstone Formation, as expressed in the 3d volume of his " Voyage en Hongrie," from p. 194. to p. 206. By AIME' BOUE', M. D. Member of the Wernerian Society, &c.

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T is a well known axiom, that nothing contributes more to the advancement of science than controversy; and, for this reason, I have thought it proper to offer you some reflections upon M. Beudant's ideas regarding the origin of the crystalline deposits which are included in the oldest secondary formations. These observations will appear to you the more necessary, that they are written with the view of contradicting the opinions of a geologist, who seems anxious to evince great theoretical impartiality, and who, on this account, inspires a great degree of confidence in the minds of his readers. Besides, were I to pass over his remarks in silence, it might seem as if I began to feel that my opinions were no longer tenable; whereas, in fact, I am every day receiving additional proofs of their accuracy.

This theoretical controversy is by no means unconnected with the progress of true geological knowledge, as is the case with too many others, for the adoption of Neptunian or volcanic ideas necessarily leads to different geognostical results: with the former the geologist cannot acquire a true idea of the singular position of the crystalline secondary deposits; he is exposed to numerous errors; he is astonished to find crystallised masses amongst arenaceous ones, and at last is obliged to suppose inechanical deposits alternating with chemical ones, of which our present degree of chemical knowledge does not shew us the physical possibility.

Before opposing my arguments to those of M. Beudant, and before proceeding to demonstrate that the origin of the crystal

line rocks of the red and coal sandstones are not so clearly a Neptunian product as this philosopher supposes, (Voyage en Hongrie, p. 195.), I must recall to mind that the opinion of the igneous origin of these rocks is founded upon their mineralogical composition and structure, upon their imbedded minerals, and upon their geognostical position, as I have shewn at full in my Essai sur l'Ecosse, p. 431. It would certainly seem that proofs, supported by observations made upon these three points by geologists of repute, might be sufficient to induce M. Beudant, as well as others, to adopt a different opinion, especially when we find that he admits, with few restrictions, the veracity of these observations; and it would seem that this being the case, the opinions advanced by the volcanists have a right to be considered as something more than "mere conjectures, derived simply from the comparison of rocks, without giving themselves the trouble of discussing the facts, or without attending to the geognostical position." (See Travels in Hungary, vol. iii. p. 195, line 16.) This remark, which has probably escaped without due reflection on the part of its author, who on other occasions manifests a becoming degree of caution, is the more surprising, that among the proofs which he enumerates, with perfect impartiality as he professes to believe, as tending to establish the igneous origin of the trap and porphyry rocks, there is not a single one deduced from the geological relations of these problematic masses..

Far be it from me to reproach this candid inquirer with partiality; yet I cannot help observing, that perhaps he has not himself seen enough of similar formations, or that he does not think he can repose entire confidence in the detailed observations which many geologists have related, of the anomalous position, and various appearances, seen in the neighbourhood of the rocks in question. In the enumeration of the proofs of the igneous origin of secondary porphyry and trap rocks, he begins with shewing the perfect identity of the secondary pitchstones with those of the trachytic countries, and follows out this similarity through nearly all its details of composition, (p. 196); but afterwards (p. 199) he tells us, among the pretended Neptunian proofs which he adduces, that this analogy of the pitchstone rocks of two different epochs, is not so complete, "when these rocks are compared under more general relations." (P. 199, line 10.)