walking by his elephant, which is laden with trophies. The last figure in a toga, beneath a palm-tree, worked in very low relief, is the likeness of the illustrious artist himself.

The figures are for the most part extremely beautiful, and from their great number the frieze extends nearly half the length of the gallery; and were there nothing else in the exhibition than this single work, every artist who visits it would consider that he had not misemployed the time devoted to its examination. The frieze was sent in by Philip Pusey, Esq., of Upper Brook Street, and to his liberality the National Repository stands indebted for several other specimens of sculpture of great excellence.

Patent Perspective Tracing Instrument. By F. RONALDS, Esq., of Croydon.

THE exhibition of last year contained Mr. Ronalds's beautiful instrument for drawing in perspective from real objects, one of which is still (from its great merit we suppose) retained in the gallery. This instrument will be found described in Vol. II., new series, p. 204. The inventor has this year sent in another drawing machine, which, if it does not excel, at least rivals the other in ingenuity and practical utility. By this architectural, mechanical, and other subjects may be accurately drawn in perspective, by merely tracing over their ground plans and elevations. The artist and draughtsman may therefore by availing themselves of its use save themselves a great deal of labour and time in obtaining correct delineations in perspective at any desired point of view and distance. By the usual process of drawing in perspective, to the labour of the operation is added the time lost in making changes in the position or distance, in order to obtain a more agreeable or advantageous view. By Mr. Ronalds's instrument these changes are obviously effected with scarcely any trouble, as it merely consists in shifting the position of the plan on the table, and tracing a few of the outlines from it. In subsequently forming the picture, all the true perspective points and lines are instantly found and drawn by simply tracing them on the plan, in perhaps one-tenth part of the time required by the common method of proceeding.

In Plate XX., fig. 4, we have given a perspective sketch of one of these instruments of a smaller size than that exhibited in the Repository, the construction of which is clearly explained by the following directions given by the patentee for its use with reference to the drawing.

DIRECTIONS.

1. Fix the sheet containing the ground plan upon the base of the instrument a, and the paper intended to receive the drawing upon the perpendicular drawing-board b.

2. To mark the true perspective place on b of any given point upon the ground plan a, apply the point of the rod c to that point, whilst the slider d rests with its universal joint at its lowest position

>

on the rod; then allow the pencil to touch the paper, by raising the little lever f.

3. If the given point be situated above the ground plan, bring the point c to its projection (or perpendicular place) on the ground plan, raise the stop g to the required height (measuring from the top of d), raised to g, and allow the pencil to touch the paper as before.

4. Any number of points belonging to a geometrical or other figure, whatever be their situations (provided that their projections on a ground plan and their heights above it be known), may be thus fixed upon the drawing-board with great rapidity and facility, and they may be united from time to time until a perfect perspective representation shall have been completed; or points thus found may be advantageously applied as guides for vanishing lines, &c. &c. &c. -But,

5. All kinds of lines situated either upon or above, and parallel to the ground plan, may be put immediately into perspective with perfect accuracy, by tracing the point c over them, or their projections on a, whilst the pencil e touches the paper; and all perpendicular lines, by moving the slider d up or down the rod between the stops g and h.

6. To determine the point of distance, draw out the tube i to a proper length; and to fix the height of the horizon, adjust k to a proper height. I and m are clamping screws.

7. When the instrument is required to be packed up, unscrew the rod n from the fork at d, and withdraw it from the two universal joints o and p. Take the arms and s, and all that belongs to them, off from the rollers on which they run, and unscrew them from the piece t. Then take out the pins v, so that the drawing-board 6, and frame w, may be turned down and lie flat upon a. Unscrew the rod

c from its base, withdraw k from its socket on i, slide i into a; then pack every thing into the space which will be left upon the base a, except the tube n, which packs in a separate case.

These machines are made of such dimensions as to serve for drawings of the largest size, and are also provided, if required, with various motions for ruling right lines, and describing mathematically, and with very little trouble of adjustment, circles and ellipses, about their perspective centres. The larger sizes are usually mounted on a table, to which is fitted a kind of treadle, &c., in order that the foot may perform the office of withdrawing the paper from the pencil, and return it instantaneously, thus leaving both hands free to work the drawing.

The price varies from ten guineas upward; it increases much less in proportion to the size than to the quantity of apparatus adapted to it.

N. B. Further details are given in a descriptive pamphlet published by the patentee.

VOL. IV. No. 82.

Q Q

1ST MAY, 1880.

Apparatus for racking Wines bright from the Lees. By MR. HILTON, of Regent Street.

THE operation of racking wines by the usual method is one of considerable trouble, and is often productive of injury to its quality, by exposure to the atmosphere, as well as a waste of its quantity. To obviate these disadvantages, Mr. Hilton (who is a wine merchant) has contrived a very simple and convenient apparatus by which the process may be performed with the greatest ease, and without the chance of deterioration or waste. This apparatus, as

by Mr. Russell, of St. John Street, West Smithfield manufactured

is represented in Plate XX. by fig. 2; the following is an explanation of its con

struction :

a is a cask of wine to be racked off; b an empty cask into which the wine in a is to be transferred; c is an exhausting pump fixed by a conical screw at the bottom into the bung-hole of the cask b; d and e are two cocks screwed into the casks near to the chimes, and communicating with each other by a syphon f, and a flexible tube or hose g. At h there is a valve to prevent a return of wine from the cask b to a. At i there is a cock to try the brightness of the wine, and at k an air-cock. The lower portion of the syphon is made of glass, that the wine may be seen during the operation.

The pump c being put in action, a vacuum is caused in the cask b, and the bung in cask a being taken out, the pressure of the atmosphere upon the surface of the wine causes the wine to be discharged, and rise in the cask b, until it gets as low in the cask a as

m.

The cock d being then half closed, and the cask a tilted, all the wine will flow out of it, the syphon preventing the air from passing during the latter part of the racking. It takes about five minutes time to rack a hogshead carefully. The distance between the casks is immaterial, which adds much to the convenience of the apparatus.

Patent Apparatus for evaporating Syrup and other Solutions. By WILLIAM GODFREY KNELLER, of Pear Street, Spitalfields.

THE novelty of the process, for which this mechanical arrangement has been designed, consists in forcing air, by means of bellows or other blowing apparatus through liquids subjected to evaporation, with the view of expediting the operation, and accomplishing it at a low temperature. The patentee states, that, in evaporating cane juice or syrup for making refined sugar, he can bring it to the proper crystallizing point by keeping the temperature between 140° and 170° Fahrenheit: that he obtains by it a great quantity of large and shining crystals, which were hitherto attainable only by evaporating in vacuo only, a troublesome and expensive process, while other methods, by exposing the sugar to a high temperature, impair the quantity, size, and brilliancy of the crystals, and form a great quantity of molasses or treacle.

At Plate XIX., fig. 5, a perspective sketch of this apparatus is given as applied to vessels of small capacity; the arrangement is,