other convenient situation. As for the fastenings, or other modes of adapting the several parts of the boiler, &e., together, I need hardly mention that I will adopt any convenient modes now in common practice in similar cases.

After the exit of the flue from the boiler, it may, if thought proper, be carried through the water tank or vessel, destined to keep up the supply for the boiler, for the purpose of heating it before it is pumped into the boiler. No doubt most of the principles laid down in the preceding descriptions have, taken separately, been heretofore known; but I claim as my own the combinations of principles therein stated.

Description of the Drawings-Plate XVIII.

Fig. 2 is a vertical section showing the internal structure of the boiler, &c. The fuel fitted for a boiler made in this way would be coal.

a, the fire-place.

b, the grate.

c, the blast-box, with a slide or door at the bottom.

d, the wind-pipe of the bellows.

e, the fuel-pipe.

f, a sliding door, shutting the fuel-pipe, and, when opened, permitting fuel to drop down from the fuel-receiver.

g, another sliding door, stopping the communication from the open air when the slide ƒ is open.

h, the fuel-receiver or box.

i, i, i, space of the boiler occupied by the water.

k, space of the boiler filled with steam.

1, steam-pipe.

m, water-gauge.

a, n, n, flue-pipes: there may be four, more or less, passing down through the bottom of the boiler, and ending in a single larger flue-pipe.

Fig. 3 represents the bottom of the boiler pierced by the flue-pipes n, n, &c.-b is the grate at the bottom of the fireplace.

n', is a larger flue, forming the exit from a flue or heat-box below the boiler; n, n, open into this flue-box, after having pierced through the bottom of the boiler.

Fig. 4 represents n, n, passing into flue-pipes, instead of passing from the boiler into a flue-box below. These flue-pipes, p, p, communicate with n'; they might, if convenient, be placed under the boiler.

Fig. 5 is a middle section of a boiler in the form of a parallelopiped, surmounted by a half cylinder. This is an excellent mode when the fuel is wood. When similar letters to those in fig. I are used, they represent portions of the boiler, &e., in-tended for similar purposes. The dotted additions to the figure VOL. IV. NO. 81. 1ST APRIL, 1830.

(b, c, d,) show how a grate, wind-box, and the wind-pipe of the bellows may be adopted.

o, is the door of the fire-place.-Ibid.

Specification of a Patent for a Machine for Ditching, or excavating Ground for Canals or other Purposes. Granted to GEORGE HENRICKS, Urbana, Champaign County, Ohio, August 5, 1829.

I MAKE a carriage or frame with four wheels, the front wheels being made and fixed in all respects like those of a common waggon. Under the body of the carriage, a plough, with the mouldboard, of any of the known forms, is fixed so as to extend along between the hind and fore wheels, the land-side of the plough standing in a line with the centre of the bed of the carriage or frame, so that the mould-board may reach nearly to one side; it is also to be depressed sufficiently below the wheels to turn up the required quantity of earth. In order to remove the earth as it is turned up by the plough, there are a number of elevators or boxes, made usually of strong sheet iron, somewhat in the manner of the elevators of a flour-mill, but much larger. These elevators are attached to each other, so as to form an endless band or chain, the boxes being connected to each other by means of strong links. These elevators are made to revolve by passing them round two revolving shafts or rollers, one of which is fixed as near to the mould-board of the plough as will allow the elevators to pass round this stands longitudinally with the carriage and plough. The other roller is fixed by proper frame-work above, and extending to a distance beyond the side of the carriage. When this chain of elevators is made to revolve as the carriage is drawn forward by horses or oxen, the earth which is ploughed up is received into the elevators, is by them raised and carried beyond the side of the ditch, so as to be delivered or thrown upon the bank, or it may be thrown into carts, or on to stageing, in the digging of canals.

In order to cause the shafts to revolve, upon which the excavators are sustained, the lower of these shafts is geared to one of the hind wheels, from which teeth or cogs project inwards, so as to take into teeth or cogs, which form a trundle upon the end of the shaft, the planes of these wheels or trundles standing at right angles with each other. The shaft I generally make square, so that the flat sides of the elevators may exactly fit them on each face as they revolve. If made round, spikes must project from them in such a way as to check the elevators, and prevent their slipping round.

In order to insure the turning of that wheel of the carriage to which the shaft is geared, its periphery or rim has a number of projecting spikes of iron to lay hold of the ground, as, without these, it would slide instead of turning.

What I claim as new in the above-described machine, is, the use of the elevators, plough, rollers, and gearing, in the manner described. And I do hereby declare that the foregoing is a full and clear description of my said machine.-Ibid.

ON THE FUSION OF TALLOW.

THE Council of Health at Nantes has been engaged in an investigation of the best means of fusing tallow, so as to avoid the injury and annoyance which arises from an abundant liberation of vapours when the ordinary method is used. Much pains has been taken in acquiring all the information possible, and numerous experiments have been made both on a large and small scale. The best process which the council has instituted, appears to consist in using, according to M. D'Arcet's suggestion, a certain proportion of sulphuric acid, and operating in close vessels. By the use of the acid, the fumes always evolved are very much altered and ameliorated in quality, at the same time that the fused tallow is improved in quality and increased in quantity, the fusion very much quickened, and the use of a press dispensed with. By the use of close vessels the fumes evolved can be either conducted to a fire-place to be burnt, or, if that may be thought dangerous, in consequence of the occasional boiling over of the melted tallow, can be conducted into a condensing apparatus, which is found readily to condense them.

M. D'Arcet uses 100 parts of crude tallow in small pieces, 50 parts of water, and one part of sulphuric acid, sp. gr. 1.848. In some small experiments a digester was used, having a pierced copper plate near the bottom to avoid the necessity of stirring; 1500 (316.5 oz.) parts of crude tallow, 750 of water, and 124 of oil of vitriol, were used, and the fumes conveyed by a pipe into a fire-place, half an hour's ebullition completed the fusion. The infusible matter, when pressed into a cloth, weighed only 96 parts, and was slightly acid. The tallow was white, hard, and sonorous, and not acid. Without the acid the same effect was not produced in an hour.

A tallow manufacturer then tried the experiment with two cwt. of tallow, using the acid, but operating in open vessels; 92 per cent. of fused tallow was obtained, and 8 of loss occurred. În a second large experiment with acid only 5 of loss occurred. The residue does not require the use of a press, but cannot be made into cakes for cattle unless previously freed from acid by washing.

Experiments made on the condensation of the vapour were found to succeed very well, and thus all fear of injury from fire is avoided. The council propose conducting the vapours into the

drains of the works, and so condensing them there-no annoyance being apprehended from the occasional return of the vapours into the building, as that effect can be counteracted by the use of stink-traps.-Annales de l'Industrie.

Remturks by the Editor of the Register.-If the above statement includes all the information furnished by the council, it is an exceedingly partial' one, as it represents only what a merchant would call the creditor side of the account. In order to decide upon the eligibility of the plan, the cost of the sulphuric acid, the extra cost of suitable close vessels, the waste of the residuary cake, &c., must be put on the debtor side; and it is then questionable how far the operators might prefer working, exposed to the fumes of sulphuric acid, without noticing the occasional sprinkling of the acid over their persons and clothes. Query, if properly-constructed furnaces and flues, to carry off the pernicious vapours, would not alone prevent the public from being inconvenienced by the tallow-chandler's process?

HYDROPHOBIA.

SIR. In all diseases, hydrophobia not excepted, prevention is better than cure. It is well known to practitioners in the diseases of dogs, that this dreadful malady chiefly proceeds from the savage custom of dog-fighting; while some of the best informed of these authorities even go so far as to doubt any instance of its spontaneous existence, or without the bite of a rabid animal at some period or other; and it is, it appears, classed with some other disorders which are only produced by communication, where the punishment of vice seems the object nature had in view. It is not, as may be seen from these observations, supposed that by the mere fighting of healthy dogs hydrophobia is created; but the complaint it is known frequently lies dormant and never suspected till discovered by its dire effect. Besides which, an habitual ferocity and propensity to biting is excited in dogs by frequent combats, which is the cause of their becoming mischievous when in a rabid state. In evidence of the truth of this persuasion, Mr. Youatt, the celebrated Veterinary Surgeon, adds his own, and informs us, "that by fighting dogs, in a tenfold greater degree than by any other breed, sabias canina is propagated.-See also the following extract from Samuel Cooper's Dictionary of Practical Surgery. Page 604, second column, says: the term hydrophobia is a palpable misnomer, for in no instance does there ever exist any dread of water" (in dogs). "On the contrary, dogs are in general very greedy after it". Same column. "There is very little of that wild savage fury that is expected by the generality of persons". Same column. "An early antipathy to strange

dogs and cats is observed." Page 605. "These animals, when actually affected with rabias, from their quiet manner, have even not been suspected of having the disorder, and have even been allowed to run about, fondled and slept with.' (See Mem. of Swedish Acad. 1777.) "Boerhaave, however, suspects that it sometimes arises from infection." Same page.

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"We learn from Dr. J. Hunter, that in the hot island of Jamaica, where the dogs are exceedingly numerous, not one was known to go mad during forty years. Page 605, line 3, second column. Although (says M. Larrey), hydrophobia is more frequent in warm than temperate climates, it is not observed in Egypt; and the natives assured us that they know of no instance in which the disorder had manifested itself either in man or animals." No doubt," it is remarked, "this is owing to the species anc dharacter of the dogs of this country and their manner of living."

It is remarked, that "the Egyptian dogs are almost constantly is a state of inaction: during the day they lie down in the shade, near vessels full of fresh water, prepared by the natives. They only run about in the night time." Then, in speaking of the Egyptian dogs (same page), it observes, that "their disposition is meek and peacable, and they rarely fight with each other: possibly all these causes may exempt them from rabias.”—Larrey in Mem. de Chis. Miletaire, tom. ii. p. 226.

"In Mr. Meynell's account, which was communicated to him by a physician, it is asserted that the complaint never arises from hot weather, nor putrid provisions, nor from any cause except the bite; for, however dogs have been confined, however fed, or whatever may have been the heat of the season, the disorder never commenced without a possibility of tracing it to the preceding cause; nor was it ever introduced into the kennel, except by the bite of a mad dog. This malady is also stated to be rare in the northern parts of Turkey, more rare in the southern provinces of that empire, and totally unknown under the burning sky of Egypt. At Aleppo, where these animals perish in great numbers for want of food and water, and the heat of the climate, this disorder is never known. In other parts of Africa, and in the hottest zone of America, dogs are said never to be attacked with madness."-Page 609, line 60, first column. "A species of hydrophobia has been known to originate from an inflammation of the stomach (Med. Essays, vol. 1.); also from the bite of an epileptic patient, or of persons in violent fits of passion."

The dangers of hydrophobia then appearing to be increased by dog-fighting, the abolition of dog-fighting and the pits where it is practised, must tend to prevent hydrophobia.

LEWIS GOMPERTZ.