ference of longitude between Ningpo and Shanghái, which are nearly N W. and S. E. of each other, we may say that the difference of latitude, 90 miles, was the breadth. We have thus 90 × 424, or 3825 square miles for its extent! Where could a cloud of 3800 square miles of fibres, alkali, and sand (for this it was by the specimens before us) come from? We have seen that it is not in the least volcanic, its animal nature putting this wholly out of the question, and all the volcanic dusts upon record are for the most part fusible and pulverulent (like pumice or obsidian), while the residuum of ours is perfectly infusible-for the little globules are, as I have stated, properly the only fusible parts, being alkaline concretions. I shall now proceed to show that though the wind was from the N. E., and the phenomena occurred while the N. E. monsoon was yet blowing, that in all meteorological probability the dust did not come from the N. E., but from the N. W. or W. N. W. For it is now a well recognised fact that the higher currents of the atmosphere are north, say at the polar circles, and become north-westerly, and gradually westerly as they approach the equator, although the trades are easterly and the monsoons alternating in their direction; and we know also that volcanic ashes and other light matters are often carried from the west to the eastward by this great upper stream of westerly wind. The fall of the ashes from the volcano of Cosseguina at Jamaica in 1835, 800 miles to the north-east of it, and consequently directly against the trade wind, is a deciBive instance of this, and I do not mention others for brevity's sake. We are assured, moreover, that our dust must have come from the land by its semi-animal constituents, and that it must have come therefore originally from some quarter to the westward of the meridian of Ningpo, for to the eastward is the ocean; and as it was brought down by a north-easterly current below, that it must have come from the northward In the north-west then seems the most probable direction to suppose it was originally carried into the atmosphere; and I shall presently show, that it is improbable it could have come from Corea or Japan. We may also note here, that Dr. Macgowan himself certifies that no dust fell at Chusan, where he was; Chusan lying north-east of Ningpo. Hence it was either too high to fall there, or it came at least from the north-west. The report of the ship I do not notice here, her position being uncertain, and no time given, and Lewchew bears about south-east from Shanghai, which would make the dust come from the north-west. The volcanic ashes and dust are, it is always supposed, and this is most probable, projected far enough into the atmosphere, or carried up by the whirlwinds which volcanic eruptions undoubtedly create, high enough to enter the upper currents of the winds, but volcanic action is out of the question here, and we must look for other causes. Frogs, fish, seeds, pollen, &c., are well known to have been carried up by * Ashes from the same volcano fell also on board H M S. Conway, in the Pacific, 1200 miles to the westward of it Jorullo, Tuxtla and St. Vincent are cases too well known to be detailed, of ashes carried to the north east whirlwinds and horizontally to great distances by currents of air before their fall, and on a larger scale we have the fine dust of the Sahara, which is often carried up and falls far out at sea about the Cape de Verd islands. There is nothing extraordinary then in supposing that this dust was originally raised by some such cause as a great storm or whirlwind, and that it might be carried by the superior current to a very great distance before it fell. It was probably also raised in a very dry state, and one cause aiding its fall might be the absorption of the humidity of the air as it approached the ocean, hair being highly hygrometric, and hence the difficulty of sup posing it to have crossed any great extent of sea, as it must have done to come from Corea or Japan. It is evidently, by Dr. Bellott's description, so light that (which appeared to him very unaccountable) it obeyed strictly, like a part of the atmosphere, the laws which regulate the deposition of dew, for it was deposited on the guns and other quickly radiating bodies, but "would not settle" on his newspaper. He forgot that the paper, being a non-conductor of the highest order, prevented the radiation from the deck in that part, and thus keeping it at a little higher temperature prevented the dew depositing, which in this case carried the dust with it. P. S. Since this paper was written, the dust has, through the kind assistance of Dr. Cantor and Mr. J. W. Grant, C. S., been examined by much more powerful microscopes than I possess, and these gentlemen, together with Major Munro, pronounce the fibres to be confervæ, and not hair. Some of these bodies may afford the ammonia in combustion, of which the smell is so strong and distinct as to lead us to suppose, without this correction, that the fibres are hair. Assuming then these to be confervæ, we have to the north-eastward as before, Japan and Corea; and to the westward, and north-westward, the Poyang, Tái, Hung-tsih, Kányn, Páuying, and other inland lakes of China, some of which might furnish vast quantities of remains of confervæ on their inundated banks and flats. In a paper by Mr. Darwin in the Journal of the Geological Society for 1845, on the fall of the fine dust in the Atlantic, which had escaped my notice, and which Mr. Laidlay has been good enough to point out to me, mention is made not only of small but of colored particles of stone, Tooth of an inch square, with some few a little larger, and much fine matter; but all the dusts examined by Mr. Darwin fuse under the blowpipe. Professor Ehrenburg finds that this dust contained no less than sixty-seven forms of Infusoria, that is of their siliceous tissues, for none of the soft parts remain. We may observe too that the whole of the dust falling on the eastern side of the Atlantic comes from the neighboring shores of Africa. These all, except the Poyáng lake. lie in the same province as Shanghái, lake Tái being nearly due west, and the others north-west of that city; the whole region between the Yellow R and the Yángtsz kiáng, lat. 31° to 34° N, along the borders of the Grand canal and easterly to the ocean, is a country of marshes and lakes, some of them saline, from which this vegetable dust might have come Ed Ch. Rep ART. IIL Sú sang yü tí ying wû Ts'iuen Tú, 伍全圖 th. A Complete Map of the military stations of Kiangsú. By CHIN and Lí. THIS map does not, as its title would seem to indicate, give us a view of the whole province of Kiángsú, but only five of its departments, namely Súchau, Sungkiáng, Chángchau, Chinkiáng, and Tái-tsang, which comprise those central and south-eastern parts that are most exposed to foreign invasion. It was, we believe, got up during the late war, and is a fair specimen of Chinese military surveys; measuring about four feet by six. The lettering and filling up are well executed for a Chinese map. Of the five departments enumerated above, it gives their boundaries, with the boundaries and names of all their subordinate divisions, as also of the rivers, lakes, and hills, and the position and outline of the cities, with the course of the Grand Canal from Chinkiáng fú to Súchau, both banks of the Yangtsz' kiáng, and island of Tsungming. The eastern line of coast, from the mouth of the Hwángpú (or Wúsung) to the frontiers of Chehkiáng,—is marked more clearly and better defined than on any other Chinese map we have seen. Along this whole line of coast there is a heavy embankment, and in some parts two; and the whole built very strong, designed to prevent the encroachment of the waters. So complete and extensive is this work, that there is no outlet for the inland waters until south and west of Chápú. But it is in a military point of view that we are to estimate the value of the map of Messrs. Chin and Lí-two civilians, who were in waiting for appointments as magistrates. In this point of view, their map is a curiosity. It has on it no date, no figures, no lines of latitude and longitude-excepting a small figure, in one corner, where are lines of latitude and longitude running parallel on a small scale, at the supposed distance of twenty li from each other. Upon the large map all the military stations are arranged "like men on a chessboard." These stations are usually indicated by flags, which makes the sheet appear like the drawing of one great camp. After taking possession of China, the Mánchú conquerors found it necessary to distribute their soldiers so as to exercise control over the whole people. Consequently, their army was divided into small detachments, and remains so to this day, though it has become so weak and spread out that it scarcely holds together During the late war, the government found it quite impossible to throw together on any given point, a strong and well-organized body of armed men. Their attempt to do this at Canton, under some of their ablest generals, was a perfect failure. So it was in other places. When brought together in the field, the soldiers were like herds of cattle, not like disciplined men. We speak here, not of the few Mánchú troops who fought unto death, bravely defending their homes—but of those native soldiers who were brought in from the provinces. We may be wrong in this opinion, but we think the most intelligent men in the government-the emperor and his cabinet, and some others-see and feel that they have now no power to arm and stand against a foreign foe. We think also, that there is reason to apprehend danger to government from its want of power to control the great mass of the people-especially in the south, where, as at Canton, they are allowed to arm and train themselves. It may be politic in the government to wink at all this, and to pretend that it is for defense against marauders; but the danger is (nor is it small) that only an occasion is wanting to develop the evils of this system. In many places, the people are in the ascendant, and they may, very soon, not only dictate to, but choose their own rulers. Of the map, further, we have only to remark, that it may help the traveler to find his way to the cities, and other remarkable or interesting localities, in these five departments. If we may rely on it, the hills nearest to Shanghái, are distant 65 li due west, and nearly 13 li north from Sungkiáng: they are in two or three clusters, called Fúng-hwáng shán, ; Sich shán, Fu-kung 鳳凰山; shán 庫公山; and Yu shán, 余山 The two latter are on the south of the other two. The Tai Hi, 太湖 or Great Lake, is distant from Shánghái 180 li due west, and is 400 í in circumference. ART. IV. Observations on the thermometer at Shánghái, exhibiting the maximum and minimum of the monthly register during four successive years, ending with 1847. THE readers of the Repository are already under obligations to Dr Lockhart for some valuable notices regarding the Climate of Sháng hai, communicated in the Reports of his hospital Since that port was opened to foreigners in 1842, they have found the climate much more healthy and agreeable than had been anticipated The opinion was very generally entertained, that the climate would not be found congenial to the constitution of Europeans. Experience thus far is most conclusive against that opinion. The country is neither a swamp nor a marsh, as some would have had us believe The surface of the plain is indeed very little above the level of the sea, but the soil above high water mark, is dry, and the atmosphere almost as pure as that at sea. Some abatement, however, inust be made, to this so favorable statement, on account of the many unnatural (except to the Chinese) nuisances inseparable from all the large towns and cities in this "flowery land." The following table has been kindly furnished us by Dr. Lockhart, made out from memoranda kept at his own hospital, in 1844 and 1845 in the southern suburbs of the city, and for the other two years in Yangking Páng. ART V Reminiscences MY DEAR B- |