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litt)*Mj but his portrait is already tltewmment of so many scientific periodicals, that had We taken it we *H&iRfiwWh'Wihflte ■appearance of imitating and borrowing fr8rn ^HftliM^'^Wld have given om' readers nothing new. It cannot also be concealed, that the President of the Royal 1ftH&ffsf/l6&§&z$ a sort of royal science. If in its pursuit he makes any discoveries 'which are useful td the multitude, they may, and welcome, have the benefit of them, but he has no appearance of labouring for the people. He brings not the science which he pursues down to their level; he stand* aloof aWftJfPdignitarles, nobles, and philosophers, and apparently takeVrio concern in the improvement of those classes for whom Out labours are intended, and to whom we look fot* support. Amidst all the great efforts which have been lately made to prdrnbte'scientific instruction among the Working classes, and aniWstall the patronage Which those efforts have found among opulent and clever men, it has been with regret that we have sought in vain to trace one exertion or one smile of encouragement bestowed on such efforts by the President of the Royal Society^ InTact, there is some reason to believe that Royal Societies of every description partake of the opinions and apprehensions of their patrons, and, like them, are not forward to encourage that Species of instruction which tends to make the great mass of mankind the accurate judges of their merits rather tr&H submissive scholars. It has certainly long been the fashion for those at the head of science to keep it in a manner inaccessible to tile profaning touch of the vulgar, letting'them see as much of it as might excite their admiration, Without enabling them to estimate its value, or to acquire it by themselves. As we have not observed any very great fceal, among those Who are at the tip-top of science, to assist the Working classes in the numerous and glorious efforts they have lately made to procure instruction for themselves, we confess a suspicion is excited that they look With no kindly eye on these efforts, and would rather have mankind for pupils than fellow-Students of the great volume of nature. If this be correct, it might perhaps be an insult to our readers to place in the front of our pages the portrait of a man who, however learned, is not learned for their utility, and who seems to take little or no interest in their improvement. It would be honouring him who takes no interest in them. ^t-'WttS MP retention to have given with the Supplement, the portrait, accompanied by a biography, of some endtien't chemist. On finding, however, that the only living English chemist who stands high above all others had been previously seized on by more than one cotemporary; that other eminent cheiriists were in the same situation, or, like Sir Humphrey,

had shown no great sympathy with the people's pursuits,— reflecting,.too, that we belong to no sect', gathering from each whatever seems good, we deemed it moie respectful to our readers, and more appropriate to the character of owr work, not to affix any portrait as a frontispiece. At the same time, to keep our promise, we shall endeavour, in the course of our ensuing volume, to give them the biography of some eminent -chemists, accompanied by their portraits.

We must now say,a few words of our intentions and our labours. The Chemist was begun under an idea that the increasing importance of the science of chemistry, as well as the increasing desireamongallclassesforaccurate knowledge, would make a weekly publication like ours acceptable to them. The support we have met with has shown that our calculations were not erroneous. Though we cannot boast of having attracted so large a share of public favour as some of our cotempofaries, we have received enough to make us acknowledge it with gratitude, and to find in it a motive for continued and greater exertions. Since the beginning of our publication, it has gone on steadily increasing in circulation, and we trust that greater efforts will ensure us a still more extensive patronage.

The object we at first proposed to ourselves was to give an outline of the principles of chemistry, with their numerous applications, as well as a history and description of all the arts which are connected with this science. In conjunction with this, it was further our intention to make The Chemist a repository of every valuable discovery, either in chemistry or the sciences connected with it, which might be made, either at home or abroad. How far the execution has corresponded with our intentions, it is not for us to say; but our readers cannot, we believe, be more sensible of our deficiencies than we are ourselves. After a mature investigation, however, we see no reason to alter the outline, of our plan, though our enlarged experience will make us in future fill it up with more precision and more in detail. The elements of our forthcoming Numbers will be the same as those of the past; but we can promise that the combinations will be more numerous and the results more striking.

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CHEMICAL APPARATUS. — by'those who are'opnient/or wh*o DESCRIPTION OF THE derive a profit from Chemistry as PLATES. a business. Many chemical exiNthe present state of Chemistry, periments may be carried on, howembracing, as it does, a prodigious ever, with a simple and cheap apvariety of phenomena, numerous paratus. As the science has adand expensive vessels and instru- vanced, indeed, it has been fonnd ments are necessary to prosecute more useful as well as more conthe study of the science with sue- venient, to operate on small than cess; and in most chemical books on large masses of matter; and directions are given for filling up a experiments, conducted on a small laboratory, which can only be done scale, have led to most of the bril

liant chemical discoveries of oar times. In fact, the most powerful instruments or agents for decomposing all bodies, the blow-pipe and the galvanic battery, can only be brought to act efficaciously on small quantities of any substance. By operating on grains of matter, the true nature of the diamond and the metallic bases of the alkalies were discovered; the gases have been compressed into liquids, and four metals before unknown were detected in the ores of platina. But though the chemist, who wants to make discQveries, may employ these powerful agents, and operate in this way, he must before have performed numerous experiments, and acquired not only great skill as an operator, but also an extensive knowledge of the science, before he could think of surpassing his predecessors and eotemporaries. There is obviously, therefore, two branches of experimenting: the one, having for its object to make discoveries; the other, to make the experimenter acquainted with the science, and enable him hereafter to pursue successfully the other branch. To prosecute the latter assiduously, an immense apparatus is necessary, which is usually only possessed in a complete state by those persons who have to teach Chemistry. Persons who wish to study this science, without being able to acquire all the necessary apparatus, must not, therefore, give it up in despair. One of the chief agents is chemical decomposition is heat; and this may, in many cases, be applied by means of a common lire-place and a pair of bellows. Again, a vast number of chemical experiments, and some of the most curious ones, are made by means of the gases, which may, when they are not greedily absorbed by water, be in general obtained by the help of a few glass retorts and phials, a small lamp, and a common bason. In the course of our labours, we shall make a point of describing a number of experiments, which may be cheaply and easily performed. We have, in

fact, selected one for the present Number; but we mean, at the same time, to familiarize our readers, by ou,r plates, with all sorts of chemical apparatus; and in the present Number we present them with a representation of the furnaces generally employed by Chemists.

Fig. 1 is a reverberatory furnace. AA is the ash-pit. BB is the body of the furnaoe. CC dome, or reverberatory roof of the furnace. DD chimney. EE door of the ash-pit. FF door of the fireplace. GG handles of the body. H aperture to admit the head of the retort. II handles of the dome. K receiver. L stand of the receiver. The retort is placed in the furnace at the aperture, and the neck comes out at the opening H.

Fig. 2 is a wind or air furnace, for melting bodies. A is the ashhole. F an opening for the air. C the fire-place, containing a covered crucible, standing on a support of baked earth, which rests on the grate. D is a passage into E, the chimney. At K is an earthen or stone cover, which may be removed to supply fuel.

Plates 3 and 4 represent Mr. Aikin's portable blast furnace, which is made out of the thin black lead melting-pots, in use among goldsmiths. The lower piece, C, fig. 3, is the bottom of one of these pots, cnt off so low as only to leave a cavity of about an inch deep, ground smooth above and below. The middle piece, or fire-place, is a larger portion of a similar pot, about six inches deep, and perforated with blast-holes at the bottom. An upper pot is added, with a hole cut in the side, to allow of the exit of smoke and flame. It has an iron stem with a wooden handle, which may be made of an old chisel. The double bellows, D, are firmly fixed to a heavy stool, the nozzle passes into C, and the air passes into the fire-place, A. No luting is necessary in using this furnace, so that it may be taken down and put up in a very short space of time. Coke or common cinders answer well for fuel; and the heat which this tlittle furnace

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