ness that a common player shews at this game, and I have often engaged with persons, who played neither so expe ditiously, nor so skilfully as this Automaton, who yet would have been extremely affronted, if one had compared them to him. You will perhaps expect me to propose some con jectures, as to the means employed to direct this machine in its movements. I wish I could form any that were rea sonable and well-founded; but notwithstanding the minute attention, with which I have repeatedly observed it, I have not been able in the least degree to form any hypothesis which could satisfy myself. The English ambassador, Prince Guistiniani, and several English lords, for whom the inventor had the complaisance to make the figure play, stood round the table while I played the game. They all had their eyes on M. de Kempett, who stood by the table, or sometimes removed five or six feet from it, yet not one of them could discover the least motion in him, that could influence the Automaton. They who had seen the effects produced by the loadstone in the curious exhibitions on the Boulevards at Paris, cried out, that the loadstone must have been the means here employed to direct the arm. But, besides that there are many objections to this suppo sition, M. de Kempett, with whom I have had long conversations since on this subject, offers to let any one bring as close as he pleases to the table the strongest and bestarmed magnet that can be found, or any weight of iron whatever, without the least fear that the movements of his machine will be affected or disturbed by it. He also withdraws to any distance you please, and lets the figure play four or five moves successively without approaching it. It is unnecessary to remark, that the marvellous in this Automaton consists chiefly in this, that it has not (as in others, the most celebrated machines of this sort) one determined series of movements, but that it always moves in conse quence of the manner in which its opponent moves; which produces an amazing multitude of different combinations in its movements. M. de Kempett winds up from time to time the springs of the arm of this Automaton, in order to renew its MOVING FORCE, but this, you will observe, has no relation to its GUIDING FORCE or power of direction, which nakes the great merit of this machine. In general I am of opinion that the contriver influences the direction of almost every stroke played by the Automaton, although as I have said, I have sometimes seen him leave it to itself for many moves together; which, in my opinion, is the most difficult circumstance of all to comprehend in what regards this machine. M. de Kempett has the more merit in this invention, as he complains that his designs have not always been seconded by workmen so skilful as was requisite to the exact precision of a work of this nature; and he hopes he shall, ere long, produce to the world performances still more surprising than this. Indeed one may expect every thing from his knowledge and skill, which are exceedingly enhanced by his uncommon modesty. Never did genius triumph with less ostentation. XLV. Method of taking impressions from Medals. CHIEFLY owing to the cost required for purchasing a cabinet of medals, it has happened, that the study of them has hitherto been confined, comparatively, to a few individuals. Another principal impediment to the cultivation of an acquaintance with them has arisen from the difficulty of understanding the inscriptions thereon, for want of a sufficient knowledge of languages; on which account in particular, this study has been condemned by the illiterate as barren and useless; but such as are acquainted with the advantages which have already resulted from these nummi memoriales, cannot hesitate a moment to assist the promotion of a more general pursuit of the subject. While colossean statues, and the hardest marbles, with their deepest inscriptions are destroyed by accident or by time, and paintings finished with the highest colours quickly fade, a medal shall survive innumerable accidents, and disclose historical facts a thousand years after statues are crumbled away; and when nothing but the names of an Apelles or a Praxiteles remain. Does not a single medal of which we are in possession, give us greater light into history, than the once famous libraries of Alexandria and Pergamus, which are now no more? From these and many other considerations, I would willingly contribute my endeavours to render this study more general, and consequently more useful. I have tried a variety of methods to enable a young medalist to collect a cabinet, which may initiate him into the knowledge of medals and coins at a trifling expense. The method of taking off plaster-of-Paris and sulphur impressions, is known to every body: the first is too soft to preserve them from injury, and the brittleness of sulphur is a great objection. I found, by forming a coat or layer of thin metal over the plaster-of-Paris, it would be a considerable defence. Tin is the cheapest and most convenient metal for the purpose, as it is sufficiently flexible, and at the same time very much resembles silver. The tin-foil I have tried, is of the same kind with that used for silvering looking-glasses. It should be laid over the medal or coin intended to be taken off, and then rubbed, either with a brush, the point of a skewer, or a pin, till it has received perfectly, the impression of the medal; the tin-foil should now be pared off round the edge of the medal till it is brought to the same circumference: the medal must then be reversed, and the tin-foil will drop off into a chip box or mould ready to receive it, the concave side of the foil, or that which laid on the face of the medal, being uppermost; upon this pour plaster-of-Paris made in the usual manner, and when dry, the cast figure may be taken out of the box or mould, with the tin-foil sticking on the plaster, the convex side being now uppermost again, in which position it is to be kept in the cabinet, after it becomes dry. To have an impression very perfect, the thinnest tin-foil should be made use of. The impressions taken in the foregoing manner almost equal silver medals in beauty, and are very durable. If the box or mould be rather larger than the impression of tinfoil, the plaster, when poured on runs round its edges, and forms a kind of white frame, or circular border round the foil, whence the new made medal appears more neat and beautiful. If this tin-foil be gilt with gold leaf, by means of thin isinglass glue, the medal will resemble gald. Having thus endeavoured to put it into the power of a young medalist to procure, in this manner, what number of medals and coins he pleases, for at most as many pence, I shall conclude, with only saying, that if by this means I may prove instrumental to the promotion of a more general knowledge thereof, by rendering the expense inconsiderable, it will be adequate to the motives of 1771, Feb. INVESTIGATOR. XLVI. Lunar Head Ache, with Remedies. MR. URBAN, I SEND you the following remarkable case, in hopes that some of your medical correspondents will take the trouble of considering, and giving their opinion upon it; and am yours, &c. W. E. "A YOUNG man, by trade a gardener, of the age of twenty-two years, has been for seven years past (at every change of the moon,) afflicted with a most violent head-ache, which entirely destroys his appetite, deprives him of rest, and renders him totally incapable of following his business. He expects the return of his disorder about twenty-four hours before the change, from which time, till the change, the pain, and the ill consequences attending it increase, then gradually decrease, and about sun-set of the second day after, he finds himself perfectly recovered. He has frequently bathed in the sea, and taken vast quantities of medicine without the least good effect, as he thinks every return of his disorder is more violent than the former. He is, at all other times, extremely hearty, and of a healthy appearance." 1771, April. MR. URBAN, Leeds, May 18th, 1771. HAVING been much afflicted with an obstinate headache from which I feared I should find no deliverance, and being now greatly relieved of that troublesome complaint, I felt more compassion for the young man mentioned in your last month's Magazine, than would probably have been excited by the recital of another case equally troublesome. My compassion for him has made me venture to give my opinion upon his case, and to offer a hint for his relief. If the case is fairly stated, and no material circumstances concealed, I should apprehend this disorder to arise from a partial plethora, and would recommend the following method of cure: Let his diet be very temperate both in quantity and quality; let no liquor be drunk stronger than mild table beer, of a good age and well hopped. It would probably be still better to drink only water with his victuals. Let him eat no flesh meat but at dinner; let his breakfast and supper be of milk, or water gruel: let his belly be kept gently open by some mild purgative taken occasionally at bed-time. Let his head be kept cool: if he wears his own hair, let it be always cut thin; if a wig, let his head be shaved all over twice a week. I would advise him not to bathe his body, but to wash his head and neck every morning with the coldest water he can procure. Let him wear nothing tight or very warm about his neck, and in the night always sleep with the collar of his shirt unbuttoned. Let him frequently wash his feet in water, new-milk warm, and wear warm stockings. And at every approach of his headache, let him apply about six leeches to his temples or behind his ears, a day or two before the usual beginning of the paroxysm. During the fit he may keep his feet in warm' water about half an hour, three times a day. In this method he should persevere for six months at least, before he Jays it aside; taking no medicines, except the aperient, occasionally, during this course. If these hints be judged worth notice, I sincerely wish the young man all imaginable success; and should be glad to know the result in some future Magazine. 1771, May. MR. URBAN, Yours, &c. W. H. CHIR. Looe, June 17, 1771. IN your Magazine for April last, there is a request to some of your medical correspondents, for their opinion on a remarkable case, from a young man under the signature of W. E. As I take delight in relieving the distresses of my fellow-creatures, I recommend to him the following powder: Take of Wild Valerian Root and Peruvian Bark in powder, each half a drachm; to be taken three times a day in any agreeable liquid, using for his common drink an infusion of sassafras shavings, or, as it is commonly called, sassafras tea. To begin taking it soon after the recovery from the paroxysm, and to defer taking it a day before its return is expected, and during its existence, that is, it is to be taken only in the intervals of the disorder. I recommend the above medicine from the experience of having cured a girl, who laboured under the same disorder three years; each successive return increasing in violence. The symptoms were exactly similar in every respect, excepting, that my patient had, during the paroxysm, or return of the disorder, a pretty free discharge of limpid serum from the eyes, mouth, and nose; and, at the decrease, an |