and has become such a favourite method, that, instead of an unguarded hortatory tone, it would perhaps be well to put in a caveat against the abuse of this most potent remedy. Of such abuse, I cannot say I have seen any example; but some friends, on whose judgment I place great reliance, have informed me that they have occasionally witnessed detraction of blood pushed to an unseasonable and improper length. This I can well believe, having felt by experience, that the great difficulty in treating this fever is to say when active evacuations ought to be laid aside. The exact decision of this point requires considerable tact, and a previous acquaintance with successive phenomena of the disease.

Purging, free purging, I have not hitherto mentioned, its necessity being so much a matter of course. A stimulus ought to be kept up constantly on the bowels, if with no other view than to relieve the head. Blisters and the cold affusion I have found to be valuable auxiliary remedies:-I call the latter by the subordinate epithet of auxiliary, for to attempt (as some have fondly hoped) to extinguish this most violent fever by it, is like attempting to extinguish the crater of mount Etna by water! It, however, reduces heat and invites sleep, and (what is of very great consequence) by its bracing power on the skin, it gives tone to the stomach, lessening nausea, and checking vomiting, a thing so much to be dreaded in every stage of this disease. With the latter view, also, I have found saline effervescing draughts, and small oft-repeated doses of calomel, highly useful.

These remedies are mentioned in succession according to their relative efficiency, but, in actual practice, their application must be contemporaneous. Bleeding, purging, cold lotions to the head, shaving the scalp, and general refrigeration by the cold bath, must be drawn up together in array against the disease, and must make a combined attack. A first or even a second disappointment must not rob us of our perseverance. Courage and constancy will in the end often succeed against great seeming odds. In short, the violent excitement must be got under by all means, ordinary and extraordinary.

I have never either tried or trusted to calomel as a siala

gogue in this disease. The blind confidence in its supposed specific power has, I believe, nearly faded away before the better lights and the more speedy results which the depletory practice has afforded.* In ardent fever, where there is a mor bid activity of the arterial, with a proportional inactivity (almost amounting to torpor) of the venous and absorbent systems, it is a matter of extreme uncertainty, whether mercurials can find their way into the system, until the paroxysm of fever is dissolved. Its action, even were it absorbed, would be rather hurtful, as favouring that depravation of the solids and solution of the fluids, which, with the effect, putrescency, are so much to be feared in the latter end of continued fevers. Upon the whole, longer time and trials have only given additional strength to the opinion which Dr. Saunders pronounced on the inutility of mercury in the endemial fevers of tropical

countries.

In the cases that came under my care, I have been in the habit of giving three or four grains of calomel after the primary stage of fever, every three or four hours, with the view of deriving from the head and viscera, by keeping up a constant action on the intestinal canal, as also to carry off sordes, and to prevent vomiting. I preferred calomel, because, from the precarious state of the stomach, more bulky or more nauseous cathartics could not, in all likelihood, be retained. When low delirium, coma, torpor, or the like, occur, it may be desirable, as a last resource, to place the system under the influence of mercury; but, even under these circumstances (though the

* An attempt has lately been made to clap up a match betwixt the deple tory and mercurial methods, and to call in the aid of both in the same case. The most respectable, if not the original proposer of this incongruous union, is Mr. Johnson, in his valuable work before referred to (see note, p. 429). What table of affinities suggested this coalition, it would be vain to conjec

ture.

However ingeniously devised this combined system may be, it will never stand. Like the famous image in the vision of the prophet Daniel, it is formed of repulsive materials: the iron and clay will not coalesce-cannot amalga- . mate, but the baser matter will crumble to dust, leaving the other part to the enjoyment of proud perpetuity. The separation doubtless will be spontaneous, and the sooner it takes place the better. 3 L

VOL. VI.

No. 24.

mouth was fairly affected), I have never been so fortunate as to see it of any avail in saving life.

Much has been said about the prophylactic virtue of this mineral in warding off the attack of fever. No one will deny that a mercurial course, by lowering the tone of the constitution, lessens the liability to this as well as all other inflammatory diseases; but some cases in point have fallen under my care, where men have been suddenly attacked with severe symptoms of the endemic, whose systems, for a week before, had been saturated with mercury on account of a venereal complaint. I therefore suspect that the influence of this metal, as a preventive of tropical fever, is like that of the eruption of prickly heat (Lichen tropicus) on the skin, founded in error: the latter, I know from repeated experience, has no other basis than hasty popular opinion.

It would be easy to extend these remarks on fever to a greater length; but I have endeavoured to confine myself to leading points, and to those opinions of late authors which seemed to admit farther elucidation. I am not altogether without hopes, that, notwithstanding the low standard of merit in which this communication must rank itself, perhaps I have furnished here and there a raw material, which may be worked up into something of utility; or a hint which, even without any such expectation on my part, may be converted by others to the improvement of our profession, for which, in my humble sphere, I trust I am not without zeal and devotedness. At all events, a delineation of the disease on a great scale, and a detail of practical facts, can never be wholly useless; and I can only say, that I have described such facts and occurrences accurately, as far as my means of information reached.

Account of an Hydraulic Machine for raising Water, called the "Water Ram." By JOHN MILLINGTON, Esq.

[From the Journal of Science and the Arts, No. II, for 1816.]

AMONG the various necessaries of life, nothing is more conducive to the health and comfort of mankind, than a plentiful and regular supply of water for domestic purposes; but this convenience is often withheld from those who live at a distance from towns, or the usual machinery for supplying water, notwithstanding they may possess it abundantly in their neighbouring springs or rivulets; which, from their low situations, preclude the possibility of using or obtaining it in any other way, than by actual transportation in carts or buckets. The expense of erecting horse-pumps or steam-engines is too great to admit of their general use in individual establishments. With a view to obviate these difficulties, and add to the comfort of those who may be deprived of the luxury of water, I beg to send you an account of a very simple self-acting engine, which is but little known in this country, though it has been several times beneficially used in France; and from the simplicity and certainty of its action, I am sure it only requires to be known and adopted to be approved.

The belier hydraulique, or water ram, as this machine was called by Mongolfier, who first constructed it about 1797, is applicable to any situation in which there is a fall of a few feet of clear water, and drainage to get rid of the superfluous quantity: and as it is simple and cheap in its construction, and requires no attendance after it is once adjusted and set to work, it is particularly applicable to the supply of houses or gardens, and pleasure grounds situated upon elevations.

The action of the water ram, as will be seen in the following description of it, is entirely dependent upon the momentum which water, in common with all other matter, acquires by moving; a circumstance which has often proved very detri mental and troublesome to plumbers and others, in fixing pipes connected with elevated cisterns.

It may have been observed by many, on turning a cock attached to a pipe so circumstanced, that the water flows with great violence; and upon shutting it off suddenly, a concussion is felt, the pipe is shaken, with a noise resembling the fall of a piece of metal within it, and the pipe is not unfrequently burst open near its end. This arises from the new energy which the water has acquired by being put in motion for a short time and then stopped, in consequence of which it makes a considerable mechanical effort against that end of the pipe which opposes its further progress.

This effect was experienced in a great degree at an hospital in Bristol, where a plumber was employed to fix a leaden pipe to convey water from the middle of the building to the kitchen below; and it was found, that nearly every time the cock was made use of, the pipe was burst at its lowest end; after making many attempts to remedy this evil, it was at last determined to solder a small pipe immediately behind the cock, which of course was carried to the same perpendicular height as the supplying cistern, to prevent the water running to waste, and now it was found that on shutting the cock the pipe did not burst as before, but a jet of considerable height was forced from the upper end of this new pipe. It therefore became necessary to increase the height of the pipe, to overcome, if possible, this jet, and it was carried to the top of the building, or twice the height of the supplying cistern; where, to the great surprise of those who constructed the work, the jet still made its appearance, though not in such considerable quantities; and a cistern was placed at the top of the house to receive this superfluous water, which was found very convenient, particularly as it was raised without trouble or exertion.

This is, I believe, the first water ram which ever had existence, the circumstance having taken place prior to Mongolfier's contrivance, though he is the first person who organised the machine and made it completely self-acting, without ever turning a cock. His construction is represented in the Plate, where A is a cistern (or part of a running brook which may be dammed up to make a head of water), and BC a quantity