specimen, however, is not to be found in Dr Hamilton's herbarium at present.

The root of the plant possesses extreme acrimony, and very marked narcotic properties. It is said to be the most poisonous of the genus, and as such has been employed in India. Wallich says, that in the Turraye, or low forest lands which skirt the approach to Nipal, and among the lower range of hills, especially at a place called Hetounra, quantities of the bruised root were thrown into wells and reservoirs, for the purpose of poisoning our men and cattle. By the vigilant precaution of our troops, however, these nefarious designs were providentially frustrated. In the northern parts of Hindustan, arrows poisoned with the root of Bikh are used for destroying tigers. The root, according to Royle, is sent down into the plains, and used in the cure of chronic rheumatism, under the name of Meetha tellia. Roots, apparently of this plant, were sent to Dr Christison from Madras under the name of Nabee. Pereira made a series of experiments on roots of Bikh, which had been kept for ten years in Dr Wallich's herbarium. These experiments are detailed in the Journal of Natural and Geographical Science for 1830, vol. ii., p. 235. The roots were administered to animals in the form of powder, and spirituous and watery extract. The spirituous extract was the most energetic. The poison was introduced into the stomach, the jugular vein, the cavity of the peritoneum, and the cellular tissue of the back. The effects produced were difficulty of breathing, weakness, and subsequently paralysis, which generally shewed itself first in the posterior extremities, vertigo, convulsions, dilatation of the pupil, and death apparently from asphyxia. One grain of the alcoholic extract, introduced into the peritoneal sac of a small rabbit, caused death in 91 minutes; and a similar quantity, introduced into the cellular tissue of the left lumbar region, proved fatal in 15 minutes. Two grains and a half of the same extract, introduced into the jugular vein of a strong dog, caused death in 3 minutes.

Explanation of Plate V.

The beautiful drawing has been executed by Mr James M Nab, Superintendent of the Royal Botanic Garden.

1. Part of a flowering panicle of Aconitum ferox. 2. Five-lobed palmate leaf. 3. Peduncle and bracts, receptacle, stamens, and the two cuculliform petals. 4. A single cuculliform petal separated. 5. Five follicles forming the fruit.

SCIENTIFIC INTELLIGENCE.

METEOROLOGY AND HYDROLOGY.

1. Fire-Ball at Bombay.-On the evening of Monday the 19th February, about half-past six o'clock, just as the sun had set, and twilight was yet strong, a magnificent fire-hall was seen to shoot across the island from south-west to north-east, and burst over the mountain range beyond. It was so large, so luminous, and so rapid in its movements, that it appeared to many as if within a hundred feet or so of the ground. It was of the most beautiful greenish-white, of dazzling splendour; on bursting, the fragments were of a strong, rather darkish, red. It was seen over the whole of the island of Bombay, and at almost every intermediate part for some 300 miles into the interior. It appears to have been at a great elevation, and, as suggested by a Poonali correspondent, was probably some hundreds of miles from the nearest spectator when first seen. The volume of the mass, the length of its course, and the velocity with which it rushed along, may from this be imagined. As above observed, when first seen at Bombay it appeared as if nearly over the dockyard; in this all the observers who noticed it in different parts of the island concur. Curiously enough, we have not been favoured with a single notice of it from any one on board the ships in the harbour; from the anchorage we have no doubt it would also appear to the eastward. At Poonah, lat. 18° 30′ N., long. 72° 2′ E., it was observed at a quarter-past six at the altitude of about 30°; it was visible from Poorundhur, twenty-six miles east of Poonah. It was observed at Aurungabad, lat. 19° 45′ N., long. 75° 30′ E., as if to the south; and from Sholapore, lat. 17° 40′ N., long. 76° E., where its appearance was most carefully described as seen in a north-easterly direction. It was also carefully observed at Surat, 21° 11' N., 73° 7′ E. It has thus been described as visible over an area of above 3° of longitude and 2° of latitude-from Bombay, 18° 53′ N., and 72° 49′ E., to Sholapore and Aurungabad; though in all likelihood it may have been observed over a much more extensive area than this, from which as yet no observations have reached us. From the explosions heard at Aurungabad it is possible that in this neighbourhood it burst. We have already alluded to the very great interest attached to notices of matters such as these, and our anxiety on all occasions to be furnished with them. With a few more notices such as those given below, we should very probably obtain the means of guessing very nearly at the distance and velocity, and course pursued by fire-balls. As we have now had abundance of time to have heard from the most remote of our outstations, and our friends have been obliging enough to respond so extensively as they have done to our call for information, we infer that the meteor was not visible much

to the southward of Sholapore or northward of Surat, or greatly to the westward of Bombay or eastward of Asseerghur-that is, betwixt the parallels of 17° and 22° and meridians of 72° and 77°, or over an area of 300 miles north and south, and as much east and west, or 90,000 square miles in all. The western margin of this space for about 30 miles is a little above the level of the sea; the eastern portion for about 250 miles varies in elevation from 1900 to 2000 feet. (From the Bombay Monthly Times, March 1849.)*

2. Great mass of Atmospheric Ice.-A curious phenomenon occurred at the farm of Balvullich, on the estate of Ord, occupied by Mr Moffat, on the evening of Monday last. Immediately after one of the loudest peals of thunder heard there, a large and irregularshaped mass of ice, reckoned to be nearly 20 feet in circumference, and of a proportionate thickness, fell near the farm-house. It had a beautiful crystalline appearance, being nearly all quite transparent, if we except a small portion of it which consisted of hailstones of uncommon size, fixed together. It was principally composed of small squares, diamond-shaped, of from 1 to 3 inches in size, all firmly congealed together. The weight of this large piece of ice could not be ascertained; but it is a most fortunate circumstance, that it did not fall on Mr Moffat's house, or it would have crushed it, and undoubtedly have caused the death of some of the inmates. No appearance whatever of either hail or snow was discernible in the surrounding district. (Ross-shire Advertiser.-Scotsman, August 11, 1849.)

3. Report on the Air and Water of Towns. By Dr Smith (Pro. Brit. Assoc.).—In commencing his report, the author says, it has long been believed that air and water have the most important influence on health, and superstitions have therefore constantly attached themselves to receptacles of the one, and emanations from the other. The town has always been found to differ from the country; this general feeling is a more decisive experiment than any that can be made in a laboratory. The author proceeds to examine all the sources from which the air or water can be contaminated. The various manufactories of large towns, the necessary conditions to which the inhabitants are subjected, and the deteriorating influences of man himself are explained. air be passed through water, a certain amount of the organic matter poured off from the lungs is to be detected in it. By continuing this experiment for three months, Dr Smith detected sulphuric acid, chlorine, and a substance resembling impure albumen. These substances are constantly being condensed upon cold bodies; and, in a warm atmosphere, the albuminous matter very soon putrifies, and emits disagreeable odours. The changes which this substance undergoes by oxidation, &c., were next examined, and shewn

If

* Mr Dawson's account of the balo observed at Pictou, Nova Scotia, arrived too late; but will appear in our next, with an engraving.- Edit.

to give rise to carbonic acid, ammonia, sulphuretted hydrogen, and probably other gases. The ammonia generated, fortunately from the same sources as the sulphuretted hydrogen, materially modifies its influences. The consequences of the varying pressure of the atmosphere have been observed; and it is shewn, that the exhalations of sewers, &c., are poured out in abundance from every outlet where the barometric pressure is lowered. By collecting the moisture of a crowded room, by means of cold glasses, and also dew in the open air, it was found that one was thick, oily, and smelling of perspiration, capable of decomposition and production of animalcules and confervæ, but the dew beautifully clear and limpid. Large quantities of rain-water have frequently been collected and examined by Dr Smith; and he says, I am now satisfied that dust even comes down with the purest rain, and that is simply coal-ashes. No doubt this accounts for the quantity of sulphites and chlorides in the rain, and for the soot, which are the chief ingredients. The rain is also often alkaline, arising, probably, from the ammonia of burnt coal, which is no doubt a valuable agent for neutralizing the sulphuric acid so often formed. The rain-water of Manchester is about 24° of hardness, harder, in fact, than the water from the neighbouring hills, which the town intends to use. This can arise only from the ingredients obtained in the town atmosphere; but the most curious point is the fact, that organic matter is never absent, although the rain continues for whole days. The state of the air is closely connected with that of the water; what the air contains the water may absorb,-what the water has dissolved or absorbed it may give out to the air. The enormous quantity of impure matter, filtering from all parts of a large town into its many natural and artificial outlets, does at first view present us with a terrible picture of our underground sources of water; but, when we examine the soil of a town, we do not find the state of matters to present that exaggerated character which we might suppose. The sand at the Chelsea Waterworks contains only 1.43 per cent, of organic matter, after being used for weeks. In 1827, Liebig found nitrates in twelve wells in Giessen, but none in wells two or three hundred yards from the town. Dr Smith has examined thirty wells in Manchester, and he finds nitrates in them all. Many contained a surprising quantity, and were very nauseous. The examination of various wells in the metropolis shewed the constant formation of nitric acid; and, in many wells, an enormous quantity was detected. It was discovered that all organic matter, in filrating through the soil, was very rapidly oxidized. The presence of the nitrates in the London water prevents the formation of any vegetable matter; no vegetation can be detected, even by a microscope, after a long period. The Thames water has been examined, from near its source to the metropolis, and an increasing amount of impurity detected. In the summary to this report, Dr Smith states, that the pollution of air in crowded rooms is

really owing to organic matter, and not merely carbonic acid,—that all the water of great towns contains organic matter,—that water purifies itself from organic matter in various ways, but particularly by converting into nitrates, that water can never stand long with advantage unless on a large scale, and should be used when collected or as soon as filtered.

4. On the Dilatation of Ice by Increase of Temperature.-Three observers have undertaken to solve this problem by independent trials made in the Observatory of Poulkowa. They have found that the linear dilatation of the ice for 80° R. is

0·0052356 (M. Schumacher sen.).
0.0051270 (M. Pohrt).

0-0051813 (M. Moritz).

The probable error in this latter determination does not exceed 0.0000190. It is a result so much the more important in the science of caloric, since the only estimate hitherto known on the same subject (that of Placide Heinrich) is almost five times more considerable.

The observations made at Poulkowa shew that the dilatation of the ice is a simple linear function of temperature, and that it is equal for all possible directions in a block of ice.

The quantity of atmospheric carbonic acid increases until we reach a height of 3365-8 metres; at that elevation is the limit of a constant maximum. Farther, at greater heights, the variations in quantity of carbonic acid are less considerable than in lower places. The immediate glacier atmosphere contains less carbonic acid than the neighbourhood. The ascending currents of air have a greater influence in the distribution of carbonic acid than the common winds.

5. The Buoyancy of the Water of the Dead Sea.-About sunset, we tried whether a horse and a donkey could swim in the sea (the Dead Sea) without turning over. The result was, that, although the animals turned a little on one side, they did not lose their balance. As Mr Stephens tried his experiment earlier in the season, and nearer the north end of the sea, his horse could not have turned over from the greater density of the water there than here. His animal may have been weaker, or, at the time, more exhausted than A muscular man floated nearly breast-high, without the least

exertion.

A horse taken into the bay could, with difficulty, keep himself upright. Two fresh hen-eggs floated up one-third of their length. They would have sunk in the water of the Mediterranean or the Atlantic.

The water of the sea was very buoyant; with great difficulty I kept my feet down; and when I laid upon my back, and, drawing up my knees, placed my hands upon them, I rolled immediately

over.