vessel, and add it to the liquor already in the eva porators.

"I claim the benefit of these letters patent, for the above described method of precipitating and separating that portion of the impurities, which, in the ordinary method of operating, remains suspended in the body of the liquor, and is only got rid of by skimming during the process of boiling; and I declare, that although I prefer to all other methods of heating for the present purpose, the method of heating in wooden vessels as before described, yet the precipitation above described may also be effected when other methods of heating are used, provided the cane juice be in other respects treated according to this specification, and provided also, the vessel in which it is intended that the precipitation should take place be cold.

"I next proceed to boil the liquor into syrup or sugar, and I prefer boiling it in vacuo by the application of steam; and in that case I prefer employing what is commonly called high pressure steam, that is to say, steam generated under a pressure of not less than twenty pounds to the square inch; steam of a pressure from twenty to forty pounds to the square inch will fully answer the purpose, but in general cases I would reccommend a pressure of about thirty-five pounds.

"I also declare that this application of high pressure steam to the boiling in vacuo, will be found highly beneficial in the boiling of any saccharine solution, for the purpose of manufacturing refined or other sugars. I apply such steam by means of a vacuum pan formed like Howard's, or any other known vacuum pan, except that there is no contrivance for applying steam to the exterior of the vacuum pan, and except so far as the construction of the vacuum pan is altered by the construction herein

after described; one or more branch pipes are carried from the steam main, which proceeds from the boiler of a high pressure steam engine; these branch pipes enter the vacuum pan at different heights, and each branch pipe terminates in a worm or coil of pipes, circulating horizontally round the interior of the vacuum pan.

"The worm or coil of pipes, when there are more than one, lie one over the other, but are not in actual contact; it will be convenient to make them all finally terminate and unite within the vacuum pan in one single pipe, by which the condensed water or waste steam is to be discharged. This discharge pipe passes through the bottom of the vacuum pan, and at a convenient distance from it with a common high pressure steam regulating cock, the use of which is well understood.

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The juice or other saccharine solution having been poured into the vacuum pan, and the vacuum having been produced, as in Howard's or any other known method, the high pressure steam is let into the branch pipes, and will circulate through them, and through the worms or coils of pipes in which they terminate, and the condensed water or waste steam will be discharged by the discharge pipe.

"I declare that I claim the benefit of these letters patent generally, for the above method of applying the high pressure steam to the boiling in vacuo, both for boiling cane juice and for boiling any saccharine solution for the purpose of manufacturing refined or other sugars.

"With respect to the liquor which has been treated in the method described, in so much of this specification as precedes the directions for boiling by high pressure steam in vacuo, I declare that if from any circumstance it should be found inconvenient to boil in vacuo, the liquor may be boiled in wooden tubes made of any con

venient size; and by the application of steam in this last case, the tubs should be fitted in the interior with a copper worm, of a size suited to the dimensions of the tubs, through which worm (having the necessary cocks to let on the steam, and allow the condensed water or waste steam to escape), the steam is allowed to circulate.

"The tubs should be placed one higher than the other, in such manner as to admit of the liquor being drawn from one to the other successively, and so into the concentrator, by means of cocks or valves; the sugar when boiled, may be drawn from the concentrator by a cock, valve, or any other convenient mea ns.

"The advantages of boiling in wooden tubs are very considerable, but I declare that I do not claim the benefit of the present letters patent for the boiling in such woodden tubs, and that I greatly prefer the method of boiling in vacuo, and by high pressure steam, as herein-before mentioned; I treat the sugar when boiled by either of the above mentioned methods, in the way now usually practised by sugar boilers, and which it is unnecessary to particularize, and I put such sugar either into hogsheads or moulds, as may be found most convenient.

And, lastly, I do hereby declare that I claim the benefit of the said letters patent, so granted to me as aforesaid, in respect only, first, of the above described method of purifying cane juice, by precipitating that part of the impurities which, according to the ordinary method, is only got rid of by skimming, during the boiling of the liquor; secondly, of the application of finings to the cane juice; and thirdly, of the application of high pressure steam, to the boiling in vacuo of cane juice, or of the saccharine solutions, for the purpose of manufacturing refined or other sugars. And with re

spect to all the matters and parts of the operation hereinbefore described (and which are already well known); I hereby disclaim all title to originality, and I declare that so far as I have described the same, I have done so only for the better explanation of the said improvement."-[Inrolled in the Inrolment Office, February, 1832.]

Novel Inventions.

The Thermidryum.—Mr. Samuel Gray, of Princes Street, Leicester Square, surgical instrument maker, has recently invented and introduced to the public a novel apparatus for warming or airing beds, which may also be applied as a sudatory for the purpose of causing extraordinary perspiration in bed, in the event of patients being afflicted with rheumatism, cold, and other complaints of that character. This apparatus is said fully to answer the purpose of a hot air or vapour bath, and as such is strongly recommended to the attention of medical men and the public in general, as its simplicity will render it available without that previous knowledge which the proper administering of a vapour bath requires.

Plate XIII. fig. 10. is a representation of this apparatus, which consists of a spirit lamp a, with a wire gauze chimney b, having at the top a number of layers of asbestos or wire gauze c, to intercept and disperse the heat from the flame of the lamp; d, d, is an outer casing or shield, also of wire gauze, which perhaps had better be made with a dome top, to prevent the bed clothes coming into close contact with the chimney of the lamp, as in that case its heat might singe them.

The chimney is mounted on a plate e, which screws upon the top of the lamp, and upon this plate is also

fixed the wire supports f,f, of the hood or fire shield, and the whole may be removed with the plate, for the purpose of lighting the lamp. When the spirit in the lamp has been set on fire, the chimney and shield must be replaced, as shewn, and the apparatus may then be safely put into the bed, that is, under the bed-clothes, and being so closed in, the air confined under the clothes will become heated to any degree of temperature required, and thereby constitute a hot air bath. This apparatus may be so placed in the bed as to cause the heated air to act upon any particular part of the patient's body or limbs, and will be found to have the most beneficial effects, under proper medical direction.

It appears to us, that if the top of the outer shield were made to take off, any chemical liquid might be placed in an open vessel over the chimney, which would throw off a vapour, and form a perfect vapour bath or fumigator. This would require very little change in the construction of the apparatus, and would be a very desirable modification.

Fire Escape. Mr. Week, brewer, Stockwell, has invented a fire-escape, with which we observe, from the daily press, some very satisfactory experiments were made very recently. It consists of a large sheet of canvass, so disposed as to admit of individuals throwing themselves into it from any height, without the danger of harm.

Improved Lavement Syringe or Stomach Pump.-Mr. Gray has also invented an improvement upon Jukes's stomach pump and lavement syringe, which we consider

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