to some of the local bleachers in this part of the country, they never had their colours in the same perfection which they now have, and which they attribute entirely to the superior effect of the steam.

1

It occurs to me, that steam might be applied for warming buildings in London, in many instances, with great advantage. For instance, the bed-rooms of large inns and hotels; as also large warehouses or shops, where a number of neighbouring buildings might be warmed from one boiler, which would save much in attendance and fuel, as well as in the cost of the apparatus. It is also well adapted to the purpose of warming churches, hospitals, and other large public buildings. I am, sir, your most obedient servant, ROBERTSON BUCHANNAN.

Glasgow,

April 2, 1808.

XLVII. On the economical Uses to which the Leaves and Prunings of Vines may be applied in this Country.

FROM experiments which I have made, I find that, on

being dried, which should be done in the shade, and infused in a tea-pot, the leaves of the vine make an excellent substitute for tea. I have also found that, on being cut small, bruised, and put into a vat, or mashing-tub, and boiling water poured on them, in the same way as is done with malt, the prunings of the vine produce a liquor of a fine vinous quality; which, on being fermented, makes a very fine beve rage, either strong or weak, as you please; and, on being distilled, produces an excellent spirit of the nature of brandy.

In the course of my experiments I found that the fer ́mented liquor from the prunings, particularly the tendrils, when allowed to pass the vinous and to run into the acetous. fermentation, makes uncommonly fine vinegar. If not intended to be distilled soon after they are lopped off, or if it should not be convenient to do so at the time, they should

be

be dried in the shade. When intended to be used, an extract should be made with hot water, as in the common process for distilling from grain.

As this is the season when the vine puts forth its leaves, and many thousand cart-loads of the prunings, where there are not goats to eat them, are yearly thrown away as useless, your stating the above in your highly interesting and useful Magazine may be of use to many of your readers, and to the public in general. I am, sir, your constant reader, JAMES HALL.

London, April 8, 1808.

XLVIII. Observations on the Nature of the new celestial Body discovered by Dr. OLBERS; and of the Comet which was expected to appear last January in its Return from the Sun. By WILLIAM HERSCHEL, LL.D F.R.S.*

THE late discovery of an additional body belonging to the solar system, by Dr. Olbers, having been communicated to me the 20th of April, an event of such consequence engaged my immediate attention. In the evening of the same day I tried to discover its situation by the information I had obtained of its motion; but the brightness of the moon, which was near the full, and at no great distance from the object for which I looked, would not permit a star of even the 5th magnitude to be seen; and it was not till the 24th that a tolerable yiew could be obtained of that space of the heavens in which our new wanderer was pursuing its hitherto unknown path.

As soon as I found that small stars might be perceived, I made several delineations of certain telescopic constellations, the first of which was as represented in figure 1, and I fixeð upon the star A, as most likely, from its expected situation and brightness, to be the one I was looking for. The stars in this figure, as well as in all the other delineations I had

* From Philosophical Transactions, for 1807, Part II.

made, were carefully examined with several magnifying powers, that in case any one of them should hereafter appear to have been the lately discovered object, I might not lose the opportunity of an early acquaintance with its condition. An observation of the star marked A, in particular, was made with a very distinct magnifying power of 460, and says, that it had nothing in its appearance that differed from what we see in other stars of the same size; indeed Dr. Olbers, by mentioning in the communication which I received, that with such magnifying powers as he could use it was not not to be distinguished from a fixed star, had already prepared me to expect the newly discovered heavenly body to be a valuable addition to our increasing catalogue of asteroids.

The 25th of April I looked over my delineations of the preceding evening, and found no material, difference in the situation of the stars I had marked for examination ; and in addition to them new asterisms were prepared, but on account of the retarded motion of the new star, which was drawing towards a period of its retrogradation, the small change of its situation was not sufficiently marked to be readily perceived the next day when these asterisms were again examined, which it is well known can only be done with night-glasses of a very low magnifying power.

A long interruption of bad weather would not permit any regular examination of the situation of small stars ; and it was only when I had obtained a more precise information from the astronomer royal, who, by means of fixed instruments, was already in possession of the place and rate of motion of the new star, that I could direct my telescope with greater accuracy by an applcaition of higher magnifying powers. My observations on the nature of this second new star discovered by Dr. Olbers are as follow.

April 24. This day, as we have already seen, the new celestial object was examined with a high power; and since

Der neue planet zeigt sich als ein stern zwischen der 5ten und 6ten grösse und ist im fernrohr, wenigsten mit den vergrösserungen die ich anwenden kann, von einen fixstern nicht zu unterscheiden.

a mag

possession of a formerly unknown species of celestial bodies, which, by their smallness and considerable deviation from the path in which the planets move, are in no danger of disturbing, or being disturbed by them; and the great success that has already attended the pursuit of the celebrated discoverers of Ceres, Pallas, Juno, and Vesta, will induce us to hope that some further light may soon be thrown upon this new and most interesting branch of astronomy,

Observations of the expected Comet.

The comet which has been seen descending to the sun, and from the motion of which it was concluded that we should probably see it again on its return from the perihelion, was expected to make its reappearance about the middle of last January, near the southern parts of the constellation of the Whale.

January 27. Towards the evening, on my return from Bath, where I had been a few days, I gave my sister Carolina the place where this comet might be looked for, and between flying clouds, the same evening about 6h 49′ she saw it just long enough to make a short sketch of its situa

tion.

January 31. Clouds having obscured the sky till this time, I obtained a transitory view of the comet, and perceived that it was within a few degrees of the place which had been assigned to it; the unfavourable state of the atmosphere, however, would not permit the use of any instrument proper for examining it minutely.

There will be no occasion for my giving a more particular account of its place, than that it was very near the electrometer of the constellation, which in Mr. Bode's maps is called machina electrica; the only intention I had in looking for it, being to make a few observations upon its physical condition.

February 1. The comet had moved but very little from the place where it was last night; and as the air was pretty clear, I used a 10-feet reflector with a low power to examine it. There was no visible nucleus, nor did the light which is called the coma increase suddenly towards the cen

.tre,

out loss of time be turned alternately either to this or to the asteroid, I found that the disk of the latter, if it were real, would be about one-sixth of the former, when viewed with a magnifying power of 460. The spurious nature of the asteroidal disk, however, was soon manifested by an increase of the magnifying power, which would not propor, tionally increase its diameter as it increased that of the planet; and a real disk of the asteroid still remains unseen with a power of 636.

May 23. The new star has advanced, and its motion is direct; its situation with respect to the two small stars a b, is given in figure 4.

Its apparent disk with a magnifier of 460 is about 5- or 6-tenths of a second; but this is evidently a spurious appearance, because higher powers destroy the proportion it bears to a real disk when equally magnified. The air is not sufficiently pure this evening to use large telescopes,

May 24. With a magnifying power of 577 I compared the appearance of the Georgian planet to that of the asteroid, and with this power the diameter of the visible disk of the latter was about one 9th or 10th part of the former. The apparent disk of the small star near ẞ Leonis, which has been mentioned before, had an equal comparative magnitude, and probably the disks of the asteroid and of the star it resembles are equally spurious.

The 20 feet reflector, with many different magnifying powers, gave still the same result; and being already convinced of the impossibility, in the present situation of the asteroid, which is above two months past the opposition, to obtain a better view of its diameter, I used this instrument chiefly to ascertain whether any nebulosity or atmosphere might be seen about it. For this purpose the valuable quan, tity of light collected by an aperture of 18 inches directly received by an eye-glass of the front-view without a second reflection, proved of eminent use, and gave me the diameter of this asteroid entirely free from all nebulous or atmospheric Appearances.

The result of these observations is, that we now are in possession