banks. Six or eight steam-boats have passed up through it. It is believed, that it will wash this year to such an extent that it will be the main channel of the

river next year. The saving in the navigation will be equally as great as that at the Red River."

MISCELLANEOUS.

Cultivation of the Tea Plant in England.-Mr. S. Rootsey, of Bristol, in a letter to the Bristol Jour nal, says, "Having found the Chinese green tea plant to be more hardy than some other shrubs which endure the open air in this neighbourhood, I have tried it upon the Welsh mountains, and found it to succeed. I planted it in a part of Breconshire, not far from the source of the Usk, about 1000 feet above the level of the sea, and higher than the limits Of the native woods, consisting of alder and birch. It endured the last winter, and was not affected by the frost of the 9th of May. It has now made several vigorous shoots, and I have no doubt of its thriving very well in time,"

Miniature Watch, Mr. Arnold, the eminent watchmaker, presented a watch to the late King, which is now in the possession of Queen Adelaide, which does not exceed, in size, half-a-crown, and weighs altogether only 5 pennyweights, 7 grains. The hour hammer weighs only half-a-grain, and the great wheel and fuzee 22 grains!

Paganini.-Dr. Bennati, of Paris, in a paper communicated to the Academy of Science, attributes the extraordinary musical powers of this wonderful fiddler to a peculiar conformation, which enables him to bring his elbows close together, and to place them one over the other-to the circumstance of his left shoulder being higher than the right-to the slackening of the ligaments of the wrists-and to the peculiar suppleness of his fingers, which he can move at pleasure in any direction.

Mr. Gurney's Steam Carriage has ceased to run between Cheltenham and Gloucester. The stoppage is attributed to the circumstance of the road having been newly Macadamized, and to the difficulty of overcoming the additional obstruction thus occa sioned.

Screws. Mr. Adcock, in the course of a recent lecture at the Manchester Mechanics' Institution, exhibited a screw of the manufacture of the late Mr. Maudsley, which in 4 feet 6 inches of length gave an inclined plane 1800 feet long. This screw had 50 threads in an inch, and yet did not throughout its length deviate from accuracy more than the 1500th part of an inch.

The Great Tom of Lincoln exists no longer-in its entire state at least. Its tone has been long impaired, and is now, by an accident, ruined beyond redemption. Some workmen were lately driving a wedge in the progress of tracing a flaw, when a large piece of the rim or skirt, weighing 6 cwt. and about 8 feet long, broke off. Tom, when entire, weighed nearly 88 cwt.; but there has been broken off at different times about 9 cwt.

Sir Humphry Davy.-Lady Davy, some time ago, gave £100 for the use of the University of Geneva, in token of her grateful remembrance of the honours paid to the remains of her late illustrious husband by the public functionaries of that city, in which he breathed his last. The Professors of the University have very properly resolved that the interest of this money shall be appropriated to the establishment of a chemical prize, to be contended for annually. "We have seen the first medal that has been struck for this purpose," says the Times," and a most cre-, ditable instance it is of the state of the arts at Geneva. One side commemorates all the labours of

Davy that can be made the subject of emblematicat description, such as the composition (decomposition ?). of the alkalis by the Voltaic pile, the safety-lamp, the (unrolling of the) Herculaneum manuscripts, &c.; ou the reverse is a wreath formed by the plaut which bears, after him, the name of Davya, with the in scription, Offerté par l'Academie de Geneve à Lady Davy. In other years it will have the name of the successful candidate for the prize." The Times farther observes, "This forms a pleasing contrast to the conduct of the chapter of a certain wealthy cathedral (in the west end of the town) who after expressing an earuest desire to have within their walls some memorial of their illustrious countryman, ultimately refused to admit a tablet of very moderate dimensions, except on payment of a charge which would have exhausted the humble fortunes of most of the philosophers of either ancient or modern times."

Lacaille's Observatory.-Lacaille had an observatory at the Collége Mazarin, or des Quatre Nations, part of which is now the Palace of the Institate. Since, a long time, it had been without observer or instruments; under Napoleon's reign it was demolished. Lacaille never used to illuminate. the wires of his instruments. The inner part of his observatory was painted black; he admitted only the faintest light to enable him to see his pendulum and his paper: his left eye was devoted to the service of looking to the pendulum, whilst his right eye was kept shut. The latter was only employed to look to the telescope, and during the time of observation never opened but for this purpose. Thus the faintest light made him distinguish the wires, and he very seldom felt the necessity of illuminating them. Part of these blackened walls were visible long after the demolition of the observatory, which took place somewhat about 1811.-Professor Mohl.

Novel Application of Horse Power. Mr. IsraelTM Abrahams, in the vicinity of this town, has a horse that will of its own accord pump a sufficiency of water for all the other horses on the farm. We have witnessed him, when turned loose in the farm-yard, go directly to the pump, take the handle between his teeth, and throw the water with as much regularity as a man would until he would pump enough for his companions and himself, when he would drink and deliberately retire. No pains were ever taken, or means used, to teach him a business which proves a great accommodation to himself, and relieves his owner of considerable trouble.-Centreville Times.

Steam Travelling.-The steam-packets between Liverpool and Dublin are now conveying persons of the labouring class at the charge of sixpence per head! On one day lately three steamers landed a thousand passengers each on the pier-head at Liverpool.

ANDERSON'S IMPROVED SLide-rest.

[We announced in our 14th volume, p. 272, that one of Dr. Fellowes' prizes to the Members of the London Mechanics' Institution for the year 1830, had been awarded to Mr. Thomas Anderson, for an ingenious improvement in the common slide-rest. We have now the pleasure of laying before our readers a description by Mr. Anderson himself of this invention, as also of some useful additions which he has since made to it. The better to enable the reader to understand and appreciate the improvements which have been effected, Mr. A. has very properly introduced into his communication a description of that particu. lar modification of the common slide-rest, to which these improvements have reference.-ED. M. M.]

The invention of the slide-rest was productive of the greatest advantages in the art of turning; by means of this ingenious apparatus, a much more perfect cylinder, or cone, or frustum of a cone, or flat surface, could be produced, and with a far greater facility, too, than was possible by the old method of turning_by hand. There was still, however, a class of bodies, viz. such as have their surfaces circular in every direction to which it could not be applied. To remedy this defect was the object of the present improvement; which has been so far accomplished by it, that bodies such as P, fig. 2, having their surface either convex or concave to the axis of rotation, may be formed with an accuracy and facility equal to that by which a cylinder could be produced by the common slide-rest. And further, where the common sliderest is only applicable to the formation of flat surfaces, the improved one is equally applicable to their formation in the form of lenses, either convex or concave.

The principle on which the improvement is constructed depends upon two geometrical propositions-first, that all angles in the same segment of a circle are equal; and, second, that if a straight line be made to move always parallel to itself with one end touching a circle, the other end will describe a circle equal in every respect to the first. This it will do whatever be the length of the line, or whether it touch the original circle internally or externally.

Fig. 1, is a plan of the improved rest;

fig. 2, a section taken through BO; and fig. 3, a cross-section of the sliders through mn. The same letters refer to the same parts in all the figures.

AA is the bed of the lathe; B, a plate fitted so as only to slide lengthways upon the bed; C, the base of the rest, which is so fitted to the last plate that it can only slide across the bed. By means of these two pieces the rest can be set in any required position upon the bed, and it is. held fast there by means of the bolt a, the head of which slides in a dovetailed groove in the base C. DD, the body of the rest, having a cylindrical socket b, by means of which it is connected with the base. This socket gives the whole rest a capability of being turned round so as to turn cylindrical, conical, or flat surfaces; and it is held fast in the required position by the set-screw c. E, is a sliding-plate working in dovetailed grooves, and is moved backward or forward by means of the screw d and handle M.

FF is a sliding-box, also working in dovetailed grooves, and it is so fitted as to slide in a direction at right angles to that of the plate E. G is another sliding piece working within the last; it carries the tool t, and is moved within the slidingbox by means of the screw e and handle H. This slider is kept steady by two setgcrews.*

KI, IL, are two similar bars with long grooves, and they are connected together by a joint at I, round which they move, and may be set to any angle; hi is a connecting bar, by which they are held fast in the position required. At K and L there are two pins, the lower ends of which are fixed to projecting pieces on the body of the rest; (one of these is seen at N, fig. 2) and the groove of the bars KI and IL slide upon their tops. The pin at I, which connects the joint of the two bars KI, IL, is fitted into the sliding-box FF (fig. 2) so as to move freely, but at the same time steadily, in its place. The top of this pin comes also through an opening in the segment which forms part of the connecting-bar hi, and it has a nut at top.

Suppose, now, that the bars KI and IL are set as represented in the figures; let the three nuts at hli be screwed fast,

The description thus far is entirely that of one modification of the common slide-rest, with this only difference, that the box FF which is here a slider, is a that care bolted fast to the plate E.

meeting had in view. These objects were generally, to give a stronger impulse and a more systematic direction to the efforts of men of science-to remove the national obstacles that now exist to the advancement of science- and to extend the intercourse with foreign philosophers. He was not of opinion that this new effort was called for by any decline in the state of science in this country; for, at no period, with the exception of that of Newton, were there names that ranked higher than those of Davy, Wollaston, and Young; and there were men still remaining amongst us whose names were no less consecrated to immortality than theirs. The decline of science in England was still further negatived, by the great increase in the number of scientific students, of scientific institutions, and of scientific publications. It was this very increase which made such a general association as he and his friends had in view so desirable. There was a greater amount of talent now devoted to scientific inquiry than formerly; and it was of the utmost importance to direct it into the least explored and most useful channels. Such an association would employ one week in every year, in pointing out the lines in which research should move, proposing problems to be answered, and calculations to be made, and setting to work, in the most profitable manner, the multitude of humble labourers in science, who were anxious to know how they might employ themselves, with the greatest advantage to science in general. The Royal Society had originally something of this kind in view; but whatever it might have effected in former times, it must be admitted, that it no longer promoted the study of philosophy by such a corporate effort as was now contemplated. The indifference and languor which had recently characterized the proceedings of that society, had led to the establishment of a number of separate associations for the cultivation of particular branches of knowledge. He lamented this dissociation of the sciences, and thought nothing could be more injurious to their common prosperity. He considered it highly advantageous to bring together men of various pursuits and objects, who had studied nature at a distance from each other, and under different aspects, in order that their scat

tered forces might be concentrated, that they might afford each other mutual encouragement and aid, and that they might organize local investigation and research. The plan for this purpose which he had been deputed by the Council of the Yorkshire Philosophical Society to submit to the meeting was, that an annual congress should be established under the title of "The British Association for the Advancement of Science ;" and that a Committee should be appointed to prepare a code of rules for the government of the proposed Association, composed of all persons now present, who had contributed a paper to the printed transactions of any Philosophical Society.

The meeting unanimously adopted both these recommendations, and it was afterwards resolved, on a Report from the Committee,

1st. That all members of this meeting, shall, on subscribing the obligation-book of the Association, become members thereof. 2d. That the fellows and members of all chartered societies be entitled to become members of the Association. 3d. That all office-bearers, and members of councils or managing committees of all philosophical institutions, be entitled to become members. 4th. That members of philosophical and scientific societies, who are recommended by their respective councils, shall be members. 5th. That £1 annual subscription, or a composition of £5, be paid by each member; and that 18 months' arrear of an annual subscription shall exclude from the Association. And, 6th. That the Committee might recommend such persons not members of philosophical societies as they should think proper to become members; but that their admission should be determined by the general body.

Lord Milton was then elected President of the Association for the first year ; the Rev. W. V. Harcourt, Vice-President; Mr. Jonathan Gray, Treasurer; and Mr. Phillips, Secretary.

After the matter of the organization of the Association had been thus harmoniously disposed of, the morning and evening sittings of the members were chiefly devoted to the reading of original papers on scientific subjects, and to the viva voce discussion of such points of doubt or inquiry as they happened to súggest. We subjoin an account of the