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ing it up, is repeatedly restored to it from the earth, through the finger of the person who makes the experiment.
The case, in short, is perfectly analogous to the instance we gave from M. De Cigna (in the part of our work above referred to); where an immense number of sparks may be succesfively taken from, and given to, an insulated plate of lead, on presenting an excited glass tube (or silk stocking) at some distance from it, and touching it; and then withdrawing the tube, and again touching the plate, fucceffively. If the insulated metal plate of an electrophorus be applied to an excited glass plate, or to one that has been charged, and then discharged, as in the Leyden experiment (or even to an excited glass globe, which it touches in little more than a point), in the same manner as it is used with the electrophorus; the same appearances will be presented.
The principal difference between the resinous and the vitreous electrophorus is, that in the former, the virtue is much more permanent than in the latter ; because resinous substances are not so liable to be affected by the humidity of the air ; and poffibly, because they possess a power of retaining the electricity which they have received from friction, or communication, much longer than vitreous substances, independent of this circumstance. M. De Volta has given his electrophorus the title of perpetual, and has considered it as preferving a kind of vestal fire, and not improperly : as it is certainly poffible, after only once exciting it by friction, to preserve its power indefinitely; by collecting a sufficient number of the sparks, when they grow weak, into a small coated vial, and then imparting to the electrophorus its former activity, by only restoring to it its own fire; by running the coating of the vial over its surface, while the knob is held in the hand.
A curious method of effecting the same purpose is described in this paper ; which consists in employing two resinous plates, and transferring the metal plate alternately from one of them to the other, and touching it after it is placed upon them. By this method, both the resinous plates have their electricity quickly increased; and the metal plate returns from each quite overcharged, so that Leyden vials may be charged by it so very Itrongly as to break them.
The singular appearances presented by the electrophorus, have been thought by some electricians to be incompatible with Dr. Franklin's theory of electricity : but the preceding illustration of the principal phenomena of that instrument fhews, that they are perfectly consistent with that system. It is true however, that, when Dr. Franklin, by means of his theory, explained the phenomena of the Leyden vial, or a charged plate of glass; it was not fufpected that, after the circuit between the two coat
ingo ings was completed, and a discharge produced, the glafs still retained a power, as we now find it does, of furnishing such a number of sparks (simply by the alternate removal and re-application of one of its coatings, &c.) as is more than fufficient to charge another vial or plate repeatedly. This quality, poffeffed by excited electrics, after they have been charged, and then discharged, particularly by those of the refinous kind, fill remains to be accounted for: unless it be alleged, that Father Beccaria has explained this property in his treatise on, what he has thought proper to call, the Electricitas Vindex; a Mort account of which will be found in our xlvth vol. 1771. Appendix, p. 555, and the page following [where, at line 12, the reader is desired to correct an erroneous transposition of the text: and instead of " this it does, in the common manner, even after it has been discharged”—to read this it does, even after it has been discharged in the common manner.”] Article 49. Obfervations and Experiments tending to confirm Dr.
Ingenhoufz's Theory of the Electrophorus; and to fiver the Impermeability of Glass to the Electric Fluid. By William Henly, F. R. S.
We do not find any thing new in these experiments, which are only diversifications of others well known. Towards the end, the Author relates an experiment made by M. Lullin, of Geneva ; which Mr. Henly considers as a curious addition to
many others that have been made, to shew the real direction of the electric matter, in the discharge of the Leyden bottle. We have frequently made remarks on the inconclufiveness of the former experiments, made with this view, both by the Author and others. They all decisively prove the effential difference between the two electricities : but not one of them-not even the present--appears to us to ascertain with absolute certainty, the real course in which the electric fluid is moving. In M. Lullin's experiment, on discharging a Leyden vial, politively, or negatively, electrified, the true direction is supposed to be indicated by the light's appearing on the upper, or the under surface of a card; and by the spot where a hole is made ; in consequence of an interruption made in the electric circuit, between the extremities of two wires, that form the communication between the inside and outside of the vial; one of which wires terminates on the upper, and the other on the under surface of the card.
PAPERS relating to MEDICINE. Article 29. On the Antiseptic Regimen of the Natives of Russia.
In a Letter from Matthew Guthrie, M. D. of Petersburgh, ta Dr. Priestley, F. R. S.
No people upon earth are, perhaps, more exposed to the operation of those predisponent causes, which terminate in the production of
the true or sea scurvy, and other putrid diseases, than the boors of Ruffia. During the long and severe winter season of that climate, they are shut up in close huts, never ventilated during fix months of the year; and where the air muít necessarily be highly phlogisticated, or rendered impure and noxious, by the breath and perfpiration of those confined in them. During this time, they live occafionally upon fish or meat, falted; and do not taste fresh vegetables : being exposed likewise, when they go abroad, to a severe cold atmosphere; the tendency of which, to produce the scurvy, is well known. Notwithstanding these circumstances, the Russian boors, as we are here told, are strangers to putrid diseases; and they owe this exemption, to an antiseptic regimen, that nature seems to have indicated to them, and which the Author minutely describes in this article.
We have already (in our Review for October, p. 279) taken notice of the Author's reflections on " the late fortunate Artention to the antiseptic Qualities of fixed Air," by Dr. Macbride, Dr. Priestley, and others; and of the strong evidence of the truth of their system, presented to us in the account here given of the antiseptic regimen of the Russian boors, and its salu. tary consequences. This regimen, which thus powerfully counteracts the baneful influence of their mode of living, confifts in the continual use of prepared vegetables in their common diet; one of the principal articles, and that which enters into the composition of most of the Russian soups, is the four cabbage; the use of which has been already adopted in the British navy. The second capital article of this antiscorbutic regimen is, a fubacid liquor, called Quass, prepared from rye flour, or ground malt; and which is not only used as a drink, but likewise, serves as a sauce to a great number of dishes.
This liquor Dr. Guthrie considers as an elegant improvement of Dr. Macbride's infusion of malt: ' for the acidulous tafte makes it highly palatable and refreshing; and probably, there may be a virtue in this species of acidity, which is perhaps the only thing that the sweet infusion wants, to give it all the antiscorbutic qualities of your four-krout; &c.; as it also abounds in the antiseptic fluid, fixed air, which recommends the other for medical purposes, and particularly as an antiscorbutic; at the same time, that the fermentation is permitted to run on until it acquires the acid taste, which I obíerve every one of the efficacious vegetable preparations used in the North, is possessed of, and what nearly seems to be the secret alone, by which these people preserve them for a length of time, and put them upon an equality with fresh vegetables, as one would be led to think by their falutary effects.'
The next articles enumerated and described by the Author, are the Ruffian rye bread, fermented with leaven; and prepared
or falted cucumbers, which have the same fourish taste with the other articles in the Russian antiscorbutic bill of fare ; and which seem to have their share also in the merit ascribed to the regimen at large :-a regimen, the Author obferves, fo confiftent, and uniformly calculated to ward off the disease that their situation threatens (even when viewed by the test of modern opinion and experience), that the most enlightened physician of our day could not have prescribed a better; and perhaps, you may think with me, that there are some articles in it, which, from their cheapness and antiscorbutic qualities, might be permitted to accompany, for trial, their old northern companion, four cabbage ; who has, I suppose, been met with ftraggling in Germany, where he was fingly able to make head against all the dangers that their climate threatened; although in our more frigid realms, it requires his whole united phalanx to keep us in safety.' Article 31. Observations on the Scurvy. By Charles De Martano,
M. D. Dated Vienna, January 14, 1778. The writer of this article adopts the same principles as Dr. Guthrie. He observes, that during an abode of many years at Moscow, he found that many gentlemen, merchants, and strangers, were attacked by a Now scurvy, having their gums foft, Twollen, and blueith, the breath ftrong, and many scorbutic spots at the legs; whilst it was rare to find among the lower people, either of town or country, a single person with these marks ;'-notwithstanding the many circumstances predifposing to the scurvy, to which the latter are subject, and which we have above enumerated.
I was many years,' says the Author, making these observations, and inquiring what it was that could preserve them from the scurvy, wbich, on so many accounts, they ought to have been more subject to than the others. It appeared to me that, exclusive of the daily use of the four cabbage, which ! consider as the most powerful of all preservatives, they were indebted for their safety to the great quantity of raw greens, such as onions, leeks, radishes, turnips, peas in the pod, and others which they eat;'- of which last, however, we thould observe, by the b;e, that they are debarred, according to Dr. Guthrie's account, during a six months winter. The people of fashion, on the contrary, cat much meat, both salt and fresh; but cat very little bread, and seldom use any greens, except a soup made of four cabbage, which they fup only occasionally,
The justice of these observations is confirmed by the trials which the Author had an opportunity of making in a large hofpital for foundlings, where there were, every winter, several fcorbutic patients. When the disease was uncommonly ftubborn,
he found a very sensible advantage from giving his little patients their vegetables in a raw state, which they had before been accustomed to eat boiled. As an addition to, and an agreeable variation in, the antiscorbutic regimen of sea-faring people, he proposes the use of four turnips, which are prepared in the same manner as the four cabbage, and are used in Austria, and several other parts of Germany.
Art. II. The History of Women, from the earlies Antiquity, to the
present Time ; giving fome Account of almost every interesting Particular concerning the Sex, among all Nations, ancient and modern. By William Alexander, M. D. 460. 2 Vols. il. 10 s. Boards. Cadell. 1779
. HE title of this work promises a great deal; and the judi
cious reader will naturally think that the writer of such a history ought to be poffeffed of a variety of talents, which are seldom united in one person; that his acquaintance with ancient and modern history ought to be very extensive; that much judgment is necessary both in the choice and in the arrangement of his materials; that he should have conversed much in the polite world; that he should possess great knowledge of the human heart, and that coup d'eil in regard to characters and manners which is absolutely necessary to the successful execution of fo difficult a task.
Dr. Alexander does not appear to us to have been sufficiently sensible of the difficulty of his undertaking; if he had, we cannot allow ourselves to think that he would have engaged in it. He has, indeed, collected a great variety of particulars relating to the treatment, the employments, and amusements, of the fair sex, in different ages and countries; and made fome pertinent observations upon them : but his remarks are generally trite, and often frivolous; his materials are injudiciously selected, and badly arranged; the language is inelegant throughout, except when he adopts the language of others. In a word, we are at a lofs to know what class of readers can receive any great pleasure from the perusal of his History. His views in publishing it we Thall lay before our Readers, in his own words :
• As the following Work was composed solely for the amusement and instruction of the Fair Sex ; and as their education is in general Jefs extensive than that of the men; in order to render it the more intelligible, we have studied the utmost plainness and fimplicity of langaage; have not only totally excluded almost every word that is not loglish, but even, as much as poslible, avoided every technical term,
• As we persuade ourselves, that nothing could be more perplexing to the sex, or to which they would pay less attention, than a long list of authors on the margin, to thew from whence we have derived our information, and as a great part of such lift would refer to books in other languages, we have entirely omitted it, and con.