gree, the number expressing the rate is to be multi- with the corresponding states of thought and feeling, plied by a constant quantity. Tyndall on Molecular Force. Professor Tyndall, in an address delivered before the Mathematical and Physical Science section of the British Association in August, 1868, made the following suggestive remarks: Every particle that enters into the composition of the muscle, a nerve, or a bone, has been placed in its position by molecular force. And unless the existence of law in these matters be denied, and the element of caprice be introduced, we must conclude that, given the relation of any molecule of the body to its environment, its position in the body might be predicted. Our difficulty is not with the quality of the problem, but with its complexity; and this difficulty might be met by the simple expansion of the faculties which man now possesses. Given this expansion, and given the necessary molecular data, and the chick might be deduced as rigorously and as logically from the egg as the existence of Neptune was deduced from the disturbances of Uranus, or as conical refraction was deduced from the undulatory theory of light. we should be as far as ever from the solution of the problem, "How are these physical processes connected with the facts of consciousness?" The chasm between the two classes of phenomena would still remain intellectually impassable. Let the consciousness of love, for example, be associated with a righthanded spiral motion of the molecules of the brain, and the consciousness of hate with a left-handed spiral motion. We should then know when we love that the motion is in one direction, and when we hate that the motion is in the other; but the "why" would still remain unanswered. In affirming that the growth of the body is mechanical, and that thought, as exercised by us, has its correlative in the physics of the brain, I think the position of the "Materialist" is stated as far as that I think the materialist position is a tenable one. will be able finally to maintain this position against all attacks; but I do not think, as the human mind is at present constituted, that he can pass beyond it. I do not think he is entitled to say that his molecu lar groupings and his molecular motions explain everything. In reality they explain nothing. The utmost he can affirm is the association of two classes of phenomena of whose real bond of union he is in absolute ignorance. The problem of the connection of the body and soul is as insoluble in its modera form as it was in the pre-scientific ages. Phosphorus is known to enter into the composition of the hu man brain, and a courageous writer has exclaimed, in his trenchant German, "Ohne phosphor kein gedanke." That may or may not be the case; but even if we knew it to be the case, the knowledge would not lighten our darkness. On both sides of the zone here assigned to the materialist he is equally helpless. If you ask him whence is this "matter" of which we have been discoursing, who or what di them this necessity of running into organic forms, he has no answer. Science also is mute in reply to these questions. But if the materialist is confounded, and science rendered dumb, who else is entitled to answer? To whom has the secret been revealed! Let us lower our heads, and acknowledge our ignorance, one and all. Perhaps the mystery may resolve itself into knowledge at some future day. You see I am not mincing matters, but avowing nakedly what many scientific thinkers more or less distinctly believe. The formation of a crystal, a plant, or an animal, is in their eyes a purely mechanical problem, which differs from the problems of ordinary mechanics in the smallness of the masses and the complexity of the processes involved. Here you have one half of our dual truth; let us now glance at the other half. Associated with this wonderful mechanism of the animal body, we have phenomena no less certain than those of physics, but between which and the mechanism we discern no necessary connection. A man, for example, can say, "I feel, Ivided it into molecules, who or what impressed upon think, I love;" but how does consciousness infuse itself into the problem? The human brain is said to be the organ of thought and feeling: when we are hurt, the brain feels it; when we ponder, it is the brain that thinks; when our passions or affections are excited, it is through the instrumentality of the brain. Let us endeavor to be a little more precise here. I hardly imagine that any profound scientific thinker who has reflected upon the subject exists, who would not admit the extreme probability of the hypothesis, that for every fact of consciousness, whether in the domain of sense, of thought, or of emotion, a certain definite molecular condition is set up in the brain; that this relation of physics to consciousness is invariable, so that, given the state of the brain, the corresponding thought or feeling might be inferred; or, given the thought or feeling, the corresponding state of the brain might be inferred. But how inferred? It is at bottom not a case of logical inference at all, but of empirical association. You may reply that many of the inferences of science are of this character; the inference, for example, that an electrio current of a given direction will deflect a magnetic needle in a definite way; but the cases differ in this, that the passage from the current to the needle, if not demonstrable, is thinkable, and that we entertain no doubt as to the final mechanical solution of the problem; but the passage from the physics of the brain to the corresponding facts of consciousness is unthinkable. Granted that a definite thought and a definite molecular action in the brain occur simultaneously, we do not possess the intellectual organ, nor, apparently, any rudiment of the organ, which would enable us to pass by a process of reasoning from the one phenomenon to the other. They appear together, but we do not know why. Were our minds and senses so expanded, strengthened, and illuminated as to enable us to see and feel the very molecules of the brain; were we capable of following all their motions, all their groupings, all their electric discharges, if such there be; and were we intimately acquainted communicated to the Royal Society the results beam. On repeating this experiment with a condensed beam of light forming a cone eight inches long, the cone, which was at first invisible, flashed suddenly like a luminous spear. The rapidity of the condensing action diminished with the density of the light. The same effects were produced when oxygen or hydrogen was employed as a carrier; when the head of the beam was sifted out through a plate of alum, or when the beam was used without sifting. That the amylic nitrite undergoes decomposition is proved by the formation of brown funes of nitrous acid. Sunlight produces similar effects. The author proves, in the next place, that the decomposition is effected by the In re refrangible rays of light, and that liquid an ylic nitrite is most potent in arresting the rays which affect its vapor. This seems to show that the absorption takes place in the atoms, and not in the molecules. The author anticipates wide, if not entire, generality for the fact that a liquid and its vapor absorb the same rays. When the tube is filled with a rare and well-mixed vapor, the electric light develops a blue color, which may be pure and deep, or milky, according to the intensity of the light. The author connects this result with that of Brücke's experiments on the colors of the sky. Various other liquids were tried with success. In many cases the condensed vapors formed extremely beautiful and regularly-shaped clouds, the particles rotating around the axes of the tube, or round other axes. The most beautiful forms appear to have been those produced by iodhydric acid.—(American Journal of Science, January, 1869.) White Gunpowder.-The Mechanics' Magazine, of August 7, 1868, speaks in terms of approval of white gunpowder, on account of the comparative safety of its manufacture and use, and its superior effectiveness as an explosive material. This substance is a white, impalpable powder, resembling flour, powdered chalk, or magnesia, in its superficial appearance. Its composition is as follows: Chlorate of potash.... 48 29 23 100 In manufacturing it the yellow prussiate nust be dried in an iron ladle until it is as white as the chlorate. The ingredients are round separately to very fine powder, and then mixed by means of a conical sieve, until they are thoroughly incorporated, but not by trituration. For small quantities a common Wedgwood mortar and pestle may be used, but they must be kept perfectly dry and clean. The operation of mixing does not take many minutes, and with these precautions is absolutely free from danger. In loading, it is treated the same way as ordinary gunpowder, being pressed down by hand, solid, but not hard. The charge is ignited in the usual way, either with a common cap or nipple, or on a rim or central-fire cartridge. No alteration is required in fire-arms in order to use it, but the cartridge-case must be little more than half its usual length, which will give the same result as double the quantity of ordinary gunpowder, but with greater quickness, penetration, and accuracy. It produces neither smoke nor flash of flame at the muzzle, on discharge, and can be used in a casemate with perfect comfort to the gunners. In actual use it does not appear to possess a bursting so much as a propulsive power. The economy of the powder is apparent when it is stated that its wholesale cost is about 86 s. per cwt., but, as its strength is said to be at least one-third greater then than that of ordinary powder, its cost may be comparatively estimated at about 60s. per cwt. Mr. Henry W. Reveley, C. E., the manufacturer of the white gunpowder (unpatented), has not been able to procure a practical trial of it from the Royal Ordnance department. A sample of three dozen rounds of Enfield cartridges, which he sent to the department for trial, were returned to him, in the original package with the seal unbroken, accompanied by a note, stating that the cartridges were not suitable for military purposes. The officials had evidently decided about them without even looking at them. Nitroglucose.-The American Journal of Science, for May, 1868, contains a paper upon this compound from the pen of Mr. M. Carey Lea. He prepares the article in the following way: two ounces of fuming sulphuric acid, two of common sulphuric acid, two of strong nitric acid are mixed. Sugar is stirred into this in the form of powder, to a thin paste. The stirring is kept up, and as fast as the nitroglucose separates in doughy masses, it is removed with a spatula, and thrown into cold water. More sugar being added will give more nitroglucose, but considerably less in proportion than the first addition. As soon as possible the nitroglucose must be kneaded up with cold water to get the acid out; otherwise (in ten or fifteen minutes) it passes to a greenish color, and decomposition commences: The removal of the adhering acid is much more difficult than in the case of peroxylin, and is an extremely disagreeable operation. The ' acid pervades the whole of the doughy mass so fully, that the fingers are stained and burned by it, nor can the whole of the acid be removed satisfactorily in this way. The best means found by the author was, to dissolve the crude nitroglucose in a mixture of alcohol and ether, and then to pour this into a large quantity of cold water with constant stirring, and violent agitation afterward. The method is not altogether satisfactory, and seems to be attended with some loss of mate rial. Prepared in this way, nitroglucose is a white lustrous body, which may either assume the doughy amorphous condition, or the crystalline, and passes from one to the other with extreme ease. When first formed by the mixed acids, it always has the doughy form. That obtained by the use of nitric and sulphuric acid was crystalline from the first. When precipitated by water from its solution in alcohol and ether, it is doughy and almost liquid, and remains so for a long time, if there is any considerable quantity of it. The best mode of preserving it appears to be under water. By standing thus it gradually hardens, and passes sometimes to a somewhat hard amorphous mass, and sometimes to a granular crystalline state. It appears to be wholly insoluble in water. A few minute grains of the crystalline form diffused through fifteen or twenty ounces of water, and did not dissolve after many hours' standing. In a mixture of alcohol and ether it dissolves as easily as sugar in water, and in such quantity as to make the liquid syrupy. Its detonating properties are but slight. If it be well dried and a match be applied, it deflagrates with a feeble flash. It has been stated by Dr. V. Monckhover that, when dissolved in alcohol and kept some time in a warm place, it undergoes decomposition, as shown by the fact that the solution then gives an abundant precipitate with nitrate of silver, which at first it did not do. An experiment made in this direction did not give the result thus indicated. A solution of nitroglucose in alcohol, containing about forty grains to the ounce, was placed in a stoppered phial and was kept in the sand-bath at a temperature of about blood-heat for nearly a month. But neither it nor a fresh solution gave a precipitate with alcoholic solution of nitrate of silver. Ozone and Antozone.-An experiment of M. Schönbein's, illustrating the simultaneous formation of ozone and antozone, is said to be the following: Into a flask of five hundred c. c. capacity, and three or four centimetres in diameter across the neck, a little ether is poured, just enough to cover the bottom, and a spiral of red-hot platinum is plunged into the vapors. It is necessary to avoid heating the flask too strongly. The platinum glows until all the ether has been destroyed. The experiment is repeated two or three times, and now the question is, to demonstrate that both ozone and antozone are formed in this slow oxidation of the ether. The first is, of course, easily shown to be present by means of the iodide of potassium and starch-paper. To show the presence of antozone, the flask is rinsed with a small quantity of ether, which will then be sufficiently charged with peroxide of hydrogen to give clearly the perchromic acid reaction. Some solution of bichromate of potash is placed in a test-tube, and a drop of sulphuric acid added, the ether with which the flask has been rinsed is then poured in, when the ethereal layer becomes colored a beautiful violet blue. The conclusion to be arrived at from this experiment is, that, during the formation of ozone, antozone is also formed-this, in the presence of water, being converted into peroxide of hydrogen. During the autumn of 1867, when the cholera was felt severely in Turin, Father Denza studied the meteorological condition of the atmosphere; he studied especially the connection between the prevalence of the disease and the absence of ozone. His observations were made at Moncalieri, rather more than half a mile from the town; the electricity was measured as well as the ozone. During the days in August and September, when the cholera was at about its height, the amount of ozone present was variable, but considerable-perhaps about the average. The electricity, however, during these days almost entirely disappeared; it is an interesting observation. Professor Frankland made this reference to the ozone question in his address to the Chemical Section of the British Association, in August, 1868: Chemists had long regarded with regret the labor expended by meteorologists on observations made with the intention of estimating ozone in the atmosphere, in the absence of any conclusive evidence of the existence of this substance in the air. It is, therefore, highly satisfactory that Andrews, to whom we were already so much indebted for our knowledge of the properties of ozone, has at length proved that the reaction exhibited by ozone test-papers at a distance from towns is in reality due to ozone. Thus the numerous observations, extending over so many years, now attain a value which they did not before possess. Microscopic Crystallography.—Mr. H. S. Waddington has read a paper before the British Pharmaceutical Society, on this subject. He says that the formation of perfect crystals depends upon the rapidity with which they are deposited. He has obtained better results, by allowing the crystals to deposit from a hot and concentrated solution, than by placing a few drops of a cold saturated solution on a clean slide and allowing it to evaporate spontaneously. When crystals are quite soluble in water, his mode of procedure is as follows: "A solution is made in hot distilled water, the liquid filtered, and a few drops poured on a clean slide, just before the crystals begin to form in the solution itself, and immediately poured off; sufficient will remain behind for the production of crystals, which will form at once. When of a sufficient size, the remaining liquor, if any, should be drained from them and the slide allowed to dry. The result will generally be a slide, evenly covered with crystals, having well-defined edges, and but few of which are agglomerated. This process answers well for alum, chlorate of potassium, nitrates of barium and strontium, potassio-tartrate of antimony, sulphate of copper, sulphate, acid tartrate, binoxalate, and quadroxalate of potassium, the strength being regulated by experience. If crystals are not very soluble in cold water, they may be allowed to separate in the bulk of the solution itself as it cools; then remove a small quantity of liquid and crystals to a slide, by means of a glass tube. The slide must be kept moving, to prevent the aggregation of the Crystallization under the Blowpipe.-It sometimes happens in experiments with the blowpipe, when borax, phosphorus, common salt, or soda, is used, that the bead, at first limpid, becomes suddenly opaque. M. G. Rose finds that this is due to the development of crystallized bodies in the interior of the mass. The crystallization is often confused, although sometimes it is very regular, and, on operating with titanium under sufficiently varying circumstances, M. Rose has been able to obtain anatase, and to effect a crystallization of the two allotropic states of the titanic acid. With felspar and phosphorus salt (by the aid of which, as is well known, silicates are reduced to silica and phosphates), he obtained crystallized quartz, confused, but insoluble in alkalies. In order to recognize the crystals, obtained under these conditions, flatten the yet warm bead and observe it under a microscope; or it may be attacked by water or an acid, in which case the residual crystals may be collected on a glass plate.-(Chemical News, vol. xvi., No. 421.) crystals, and the superfluous liquid removed by applying blotting-paper to the edges of the side. For hippuric acid, the solution, when on the point of crystallizing, should be poured on a cold slide, and, when the crystals have formed, the remaining liquid should be poured off, and the slide allowed to dry. Sugar, citric and tartaric acids, and all substances very soluble in water, may be obtained in crystals by making a concentrated solution, filtering it, and then pouring it on a slide, taking care that only a thin layer of liquid remains, which should be allowed to dry in the air. To obtain crystals from sulphate of iodoquinine or 'Herapathite,' the author mixes three drachms of spirits of wine, and one dachm of acetic acid, in which he dissolves ten grains of bisulphate of quinine. He then purs ten or fifteen drops on a slide, and alds a drop of tincture of iodine. When clear he pours it from slide to slide as long as the liquid holds out. The best method of obtaining ric acid in crystals is, to allow eight or ten o-unces of urine to stand some hours, after the addition of two or three drachms of acetic acid. In a day or two the crystals will have grown larger, when the bottle should be shaken, to detach them from the sides; then wash them with distilled water, acidulated with acetic acid. To obtain the rarer forms, it is requisite to allow the crystals to deposit quickly, which may be done by making a solution of urate of sodium, by boiling uric acid with solation of caustic soda, until no more is taken up. If one or two drachms of this are put into eight ounces of urine, and a small quantity of acetic acid added, not more than sufficient to neutralize the soda, very perfect crystals will be obtained. Another deposit found in urine is the phosphate of ammonium and magnesium, or triple-phosphate, which may be prepared in prisms by dropping about twenty-five or thirty grains of carbonate of ammonium into eight or ten ounces of urine, and allowing it to remain quiet for some hours. When the crystals are of sufficient size, the bottle may be gently shaken and the urine poured off. This deposit may also be obtained in stellate crystals by adding a drachm and a half to two drachms Of carbonate of ammonium to urine, and allowing it to stand. The crystals should be washed with distilled water, to which a little liquor ammonia has been added. Calcic oxalate may De obtained by dropping a single small crystal of Oxalate acid into eight or ten ounces of urine, and leaving it at perfect rest for some hours. Mr. Waddington has also obtained good results from salicin, by pouring a saturated solution in cold water on a slide, holding it over a fame until it is at the boiling-point; then pouring off the slide, when only a viscid film will remain. This must become quite cold, and the under surface held close to the flame of a gas-jet. The moment it begins to Crystallize it must be removed a few inches from the flame, or else it will fuse." lamp or Crystallization of Sulphur.-M. Schützenberger, of Paris, has made an interesting experiment upon the crystallization of sulphur. He filled a matrass, of a capacity of one hundred and fifty or two hundred grammes, with refined sulphur, commercially pure, so that, when fused, the liquid occupied the whole of the space below the neck; the upper part of the neck was drawn out into a capillary tube, which was twisted several times, but left freely open to the atmosphere. The sulphur being melted in a bath of oil heated to 120°, the flask was placed in water heated to 95°. In these conditions, the sulphur remains perfectly fluid for hours, even when occasionally moved and drawn out of the hot water. If the temperature be made to fall very slowly, transparent crystals, possessing the same density as the melted sulphur, form either on the surface or in the midst of the fluid at about 90°. The mass of crystals gradually augments, but with great slowness; sometimes they are isolated, sometimes united in groups of two, three, four, etc. The amount of crystals being considered sufficient to separate them, the matrass is sharply inverted, so as to cool and solidify the melted sulphur in the neck. Thus the crystals are separated from the rest of the sulphur, and only remain suspended by their peaks. They are transparent and remain so indefinitely; in form they are octahedral and bear close resemblance to natural crystals. Measurement of the angles has confirmed their identity. The experiment is surer when two or three drops of sulphide of carbon are added to the sulphur before fusion; the phenomenon takes place, however, independently of this admixture. By this experiment of M. Schützenberger's it is proved that melted sulphur crystallizes below 100° in octahedra of the fourth system without the aid of any solvent. The facts will probably be turned to account in the study of the formation of natural crystals. The question of how and under what circumstances sulphur will crystallize from substances containing it, was referred to in a recent murder trial at Versailles. The victim had been poisoned, it was said, by lucifer matches. The chemist stated, that after a scrupulous examination of the exhumed matter (interred two years) he had failed to detect phosphorus, probably volatilized or oxidized long ago, but he had separated several pieces of melted sulphur, which he exhibited. From these facts he concluded that chemical matches must have been present, for these traces of sulphur, though very small, could not occur in culinary or pharmaceutical preparations. The question was then put-did he not know that sulphur similar to that which he had exhibited was found in deposits of fecal matter which had undergone a certain fermentation in the air? and upon this point, the finding of sulphur perfectly crystallized or in concreted masses, in the old deposits in the sewer of Montfauçon, was cited; the specimens of sulphur here referred to are preserved in one of the public museums. Great doubt was thus thrown upon the source of the sulphur; indeed, judging from the chemist's evidence, he would appear to have argued farther than the experimental data justified him in doing. The prisoner was acquitted. Industrial Preparation of Oxygen.-M. Gondolo has made some improvements in M. Boussingault's process of extracting oxygen from the air by means of baryta. M. Boussingault, in 1852, found that in passing a current of air over baryta, heated to dull redness, oxygen was subtracted from the air, and binoxide of barium formed, and that, upon then raising the heat to bright redness, the oxygen was set at liberty so easily that the oxygen might be first absorbed and then evolved ad infinitum. M. Gondolo has made, in carrying out the details of the process, certain changes which admit of oxygen being prepared upon a manufacturing scale. For the porcelain tubes he substitutes iron ones, which may be made either of wrought or cast iron. Internally a coating of magnesia is applied, and externally asbestos, so as to diminish the porosity of the tube and the consumption of fuel. These tubes are arranged in a brick furnace having dampers, by means of which the temperature may be changed at will, and dull redness and bright redness easily obtained. To the baryta a mixture of lime, magnesia, and a small quantity of manganate of potash is added; this prevents fritting of the material. M. Gondolo says that he has made one hundred and twenty-two alternate operations, and that the atmospheric oxygen and nitrogen are easily separated upon an industrial scale; the apparatus has been at work during six months, and fulfilled its purpose thoroughly. The process is patented. (Paris Cor. of Chemical News.) Oxychloride of Silicium.-MM. Friedel and Ladenburg have reported to the French Academy their discovery of this compound. In passing chloride of silicium through an empty porcelain tube, or one filled with fragments of felspar, heated to a temperature approaching the point of fusion for that mineral, and distilling, they observed that the product condensed at the extremity of the apparatus was a liquid less volatile than the chloride. By repeating the operation a great number of times with the more volatile portions, a notable amount of a liquid boiling above 70° is obtained. This product submitted to fractional distillation is easily separated into chloride of silicium and a liquid chiefly boiling between 136° and 139°. Limpid and fuming in the air, this liquid bears great resemblance to chloride of silicium; it is likewise decomposed by water energetically, Analyses were made by introducing weighed bulbs, full of the liquid, into flasks containing a certain quantity of water; breaking the bulbs afterward, almost the whole of the silica, when sufficient water was present, remained in solution. The acid liquid, saturated with ammonia, was evaporated on the water-bath; the residue dissolved in water and filtered gave on the one side silica mixed with the glass of the bulb, on the other a solution in which the chlorine was determined. The numbers obtained lead to the formula Si2OCl., from which the new body is seen to be an oxychloride of silicium. The tube is Iodide of Silicium.-Mr. M. C. Friedel has given to the Chemical News the result of his recent studies of iodide of silicium. He makes it by the following process: In a tube he places crystallized silicium. heated to redness, and through it is passed the vapor of iodine, along with a completely desiccated carbonic acid. If the distillation of iodine is rapid, or if the silicium does not fill the tube, the product obtained is mixed with much iodine. But with a tube of sufficient length, and the exercise of caution, the crys tals sublimed in the cool part of the tube will be white, and the liquid proceeding from their fusion yellowish. The product thus obtained, purified when necessary from iodine, by solu tion in sulphide of carbon and agitation with mercury, may be distilled in a current of carbonic acid without decomposition. Not so in the air, where its vapor, on being heated, catches fire, and burns with a red flame, emitting much iodine vapor. The product, distilled in carbonic acid, is colorless, or slightly yellowish. Its boiling-point is 290°, and at 120.5° it solidifies and crystallizes into a mass, having a watered appearance (moire) which is nearly always rose-colored, owing to a slight decomposition which takes place at the moment the tube is sealed. In those parts of the vessel which were merely moistened by the liquid, dendrites are formed analogous to those of chlorhydrate of ammonium. The crystalline form of iodide of silicium is cubic, and it may be obtained either by sublimation, evaporation, or refrigeration of its solution, in small regular octahedra or groups of octahedra, which are transparent, colorless, and incapable of action on polarized light. |