206

8

4

M

1

2

Let в be the same battery, and m, m, m, m, be four electro-magnets exactly similar to the former one. Let half the current go through the magnets m and m, and the other half through m and m; then it will be found that each magnet sustains 2 lbs., or the whole four will bear 2 n lbs., or twice the weight sustained before.

And the same process may be repeated or varied ad infinitum. Can we then get infinite power out of a finite source of force? Yes; but, on this condition, that what we gain in power we lose in time; for the current would take twice as long to traverse the second circuit, and, therefore, it takes double the time to produce double the magnetic power. But the electric current is so rapid that this difference of time is inappreciable within any practical limits.

It may be said that in this arrangement we are doing no work. This is so far true, that we are only doing work while the soft iron is being magnetised, and pressing the iron keeper to itself. But this work is being done every time that the circuit, after being broken, is closed; and the circuit may be broken and closed so many times a second that the number is practically illimitable, and hence the amount of work which can be done by a given battery is illimitable. The only question is a question of first cost of machinery.

What becomes of the electric power in the interval between the moment when the soft wire becomes fully magnetised, and the moment when the circuit is broken? It is wasted in producing heat in the wire,* and the smaller this waste the greater the available magnetic power.

All the relations given in our text-books between amounts of electrolysis, electric force, heat, and motion,

* Since writing the above, I have found strong reasons for doubting the truth of this statement; but I propose shortly publishing a full discussion of this point.-H. H.

CHEMICAL NEWS, Oct. 28, 1870.

The author

are true only partially and in particular cases. hopes, at some future time, to show how far they are true, and where they fail.

According to Joule, Favre, Silbermann, and others, the consumption of a gramme of zinc in a battery produces about 550 units of heat (each unit being able to raise about 423 grammes through 1 metre), or about 232,650 grammes raised I metre. But Faraday said a grain of zinc produces more force than any flash of lightning; and Weber and Kohlrausch say that the force which decomposes 9 milligrammes of water-that is, the force of oxidation of 1 milligramme of hydrogen, can raise 208 tons 1000 metres ! and a gramme of zinc will produce thirty times as much heat as a milligramme of hydrogen.

At a future time, the author will show the fallacies involved in all these calculations. Meanwhile, enough has been said to set aside the à priori argument against electro-dynamic engines-namely, that as a pound of zinc can only produce a certain amount of heat, and a pound of carbon, which is much cheaper, can produce more heat, therefore electro-dynamic engines can never compete with steam engines. In fact, it is a question of prime cost of machinery, and skill in construction, and not of cost of working.

ON THE CHEMICAL COMPOSITION OF THE BONES OF GENERAL PARALYTICS.*

By J. CAMPBELL BROWN, D.Sc.,

Lecturer on Chemistry and Toxicology at the Liverpool Royal Infirmary School of Medicine.

IN consequence of the large share of public attention which has lately been attracted to the occurrence of fractures of the ribs among the patients in our lunatic asylums, several specimens of ribs of general paralytics have been sent to my laboratory.

The general appearance of all of them is so unlike that of the ribs of healthy adults, that I have been induced to submit average samples of them to analysis. In the accompanying table, the first four columns of figures show the composition of these samples.

I. Consisted of six ribs, which had all been fractured in a straight line downwards, and had completely united again by firm bony union; they showed slight callosities; some of them had again been fractured more recently, and had only imperfectly united; they contained an unusual amount of fat. Portions of the ribs were removed and were freed from fat before they were submitted to analysis, and the remaining portions were handed to the curator of the Museum of the Liverpool School of Medicine. The age of the subject from which they were taken was thirty-nine.

II. These ribs were not fractured, nor did they contain much fat; they were, however, thinner than usual. They were taken from the body of a patient who had suffered from mania with general paralysis.

III. Consisted of one rib only; it was slender and rough, and jagged on the edges, but had not been fractured. It was taken from the body of a woman aged forty.

IV. Shows the average proportions of organic and earthy matter in several samples not more completely analysed, which were remarkable only for being less perfectly developed than the ribs of healthy adults; some of these had been fractured and perfectly united, others were entire.

For comparison with these, I give the composition of the femur and tibia of a nine-months' foetus in column V., and of the bones from a case of osteo malacia in column VI.

VII. Is calculated from the analysis of a healthy adult tibia, by Valentin.

* Read before the British Association, Liverpool Meeting, Section B.

It will be observed that the ratio of organic constituents to earthy matter is much greater, and also that the ratio of lime to phosphoric acid is distinctly less in the ribs of paralytics than in those of healthy adults.

There are the same differences between the composition of healthy ribs and those of paralytics as between the composition of the adult large bones and those of the fœtus. And, generally, the composition in cases of paralysis approaches that observed in cases of osteo malacia. Whether the defects in the ribs of paralytics are due to arrested development, or to degeneration of the fully developed bone, it will require further experiments upon carefully selected cases to prove; but from the evidence already obtained, I am led to conjecture that both causes will be found to operate, but principally the former.

I exceedingly regret that more analyses have not been made before this time; it will be readily understood that specimens of bones cannot be made to order; we must wait until they can be obtained at post mortems; and I propose to continue the enquiry when more specimens have been obtained.

The result of the analysis quoted is suggestive, rather than conclusive, as to the condition of the bones in patients the subject of general paralysis, and it is clearly unsafe to generalise from a few examples. These analyses, however, form a first instalment towards determining whether the statements that have been made as to the peculiar liability to fracture of the bones in certain forms of insanity holds good as a general rule.

ON THE CALORIFIC POWER OF HARE'S

BLOWPIPE.

By HENRY WURTZ.

OBSERVING in a lately received issue of the CHEMICAL NEWS, my first partial reply to Dr. W. M. Watts, I am encouraged to enclose a supplementary note in completion of said reply, lately printed by me in my own journal (The American Gaslight Journal). I perceive that Mr. Watts has also added a rejoinder to the aforesaid partial reply, which calls for a further continuation of the discussion on my part. I am gratified by the courteous tone of Dr. Watts's rejoinder, which I shall emulate.

Dr. W. M. Watts, in his strictures on the discussion

of Professor Silliman and myself of the "Calorific Powers This specimen also contained fat which had not been removed before analysis.

Dr. Watts's other points were probably sufficiently met in my reply, but this point was at that time expressly reserved, as looking to considerations which had already led to some little oral discussion between us, and with others.

Having had no opportunity, as yet, for that mature deliberation, in conjunction with Prof. S., that I desired to have, before going into print further on these questions of specific heat, and feeling that delay may cause misconstruction, I have given to them individually such consideration as I have had time for, and have decided to present a reply to Mr. Watts, in anticipation of our joint reply. In the preparation of the latter, arranged for an early day, any new lights that may appear in the interim, will of course be available.

Previous to the date of the first publication of our joint paper in the course of conversation with Prof. H. F. Walling, he made to me the suggestion that it was possible our formula ought to be so modified as to read34462-9 (537+51*95)

=6743°

4'3245 leading, as will be seen, to the same figure as that of Dr. Watts. Prof. Walling, however, expressed himself as by no means sure of his view, as he had given no especial study to the subject, and offered it merely as an hypothesis. The apparent coincidence here gives more interest to the subject.

It is to be observed that Dr. Watts's formula supposes the temperature of the pound of hydrogen started with, in the combustion, to have been zero, and, further, that each of the nine pounds of water (as water) must have absorbed and retained 100° of sensible heat. Hence his figure 637°; which he diminishes, however, by 48 05°, for reasons which, as follows from the context, arise out of the difference between the specific heats of water and steam. The only conclusion I can draw from this is that Dr. Watts believes it requires an absorption of 51.95° of sensible heat from 1 pound of water at 100°, to convert it into 1 pound of steam at 100°, plus the 537° of latent heat generally admitted as the actual result of experiment; or, as may otherwise be stated, follows from Dr. Watts that the latent heat of steam at 100°, instead of 537°, is really 537° +5195588 95°. I prefer as yet to stand by the experiment, until I receive from Dr. Watts some clearer explanation.

In the case of Prof. Walling, whose doubtfully submitted hypothesis also arose out of the consideration of the difference between the specific heats of water and steam, in the first place, it is clear at a glance, that the coincidence in the resulting figure is not accidental; for 637-48'05=537+51*95; and from this formula it is still more evident that, in addition to the 537° known by experiment to be all the heat that actually becomes latent in the conversion of one pound of water at 100° into one pound of steam at 100°, 5195° more must be supposed to become latent, leaving but 48 05° of the sensible heat of the boiling water to remain sensible in the steam, and again increasing the latent heat of steam to the hypothetical number, 588 95°.

There must be a reason for every error (if this be one, in seeking for the cause of this one, it seems to me to arise as I cannot but conclude), as well as for every truth; and from a notion of specific heat, as absolute quantities, instead of mere ratios. The name is good, as it means

208

merely that different species of matter are differently affected by equal additions of heat; and specific heats are merely the ratios of these differences. When a body changes its state, as from water to steam, the 537' required to produce this change of state produces also a change of specific heat. The sensible heat remains unaltered. The 537° must come from external sources. Steam is different in species from water, and possesses a different specific heat ratio. Time fails for a fuller exposition of this subject now.

With regard to our formula for the total heat of Hare's blowpipe, though Dr. Watts's correction, as I have endeavoured to show, does not appear to me sustainable, there has occurred to me a small correction, necessary to precision, which I shall call attention to, here and hereafter, for the reason that the principle on which it depends, is, in its application to combustible gases, becoming now of practical importance. This is merely a correction for the temperature of the hydrogen before burning, which, for simplicity, Silliman and Wurtz assumed to be zero. If this temperature is the ordinary one of 60° F. (= 15.6° C.), at first glance it might appear necessary merely to add 15.6° to the 34462 in the numerator of our fraction. This would involve an error, however, which, though trifling here, would be very important in cases where the combustible or supporter of combustion is highly heated beforehand. Such cases I will discuss at an early day hereafter. Here I shall merely explain that in the oxyhydrogen flame, we must first calculate the mean of the specific heats of the gases in combustion, thus

gas in these, so as neither to overcharge them (when the excess would escape through the water-pipes and tank) nor allow them to become empty.

From the upper part of the gas reservoirs or stationary cylinders just described, service pipes are carried down into the caisson, and there distribute to the outer ends and middle points of each chamber where the usual jets and lime holders are permanently attached.

The light afforded by this means is excellent, and if it is possible (as we imagine it must be) to whiten the roof and upper part of the caisson walls, its efficiency would be very largely increased. In looking from one chamber of the caisson into another, where one of the lights was near the doorway but out of view, we were strongly impressed with the idea that daylight was entering through some unexpected opening. The foggy state of the air causes a considerable loss of light, so that at a distance from the burner this is less effective than one might expect. With the number of lights now in use, however, the supply is sufficient, and candles are only required in a few locations sheltered from the direct rays. We feel sure that a whitening of the roof and walls would be of very great service.

It is proposed to let the gas reservoirs descend as the caisson goes down, building around them a coffer-dam, by which means the hydrostatic head will be increased exactly as the air pressure in the chambers is raised, so that a constant difference will be maintained.

The greatest depth to be reached being 40 feet, the maximum pressure required, according to the present standard, would be about 36 pounds, and the pressure in the small charged cylinders being 225 pounds, no difficulty will be found in introducing the gas from them. The pressure now used is, however, largely in excess of what is required, as one or two pounds above that in the caisson would be quite sufficient to secure the steady burning of the lights. In fact, we are sure, from previous experience, that the pressure between the stop-cocks of the jets and the flames is now not more than a small fraction of a pound per square inch in excess of the surrounding compressed air. Were there any object in reducing it, we are

RIVER BRIDGE.*

ON page 190 of the last volume of the CHEMICAL NEWS, the fact was alluded to that arrangements had been made with the New York Oxygen Gas Co., to supply gas for a series of lime-lights by which the six compartments of this huge caisson might be lit.

We can now from personal inspection describe the arrangements by which some fourteen of these lights are kept in constant and successful operation. The plan of these adjustments is we understand, chiefly due to Mr. Martin, Assistant Engineer. To secure a steady supply of each gas under constant pressure, two large sheet-iron cylinders, about 21 inches in diameter and 6 feet high, are placed upon the top of the caisson, and are connected by iron piping with a water reservoir on the roof of an adjacent building, by which means a hydrostatic column or pressure of some 16 pounds per square inch is made available. These cylinders being filled with water, the gas is let into them from the portable cylinders supplied by the Oxygen Co., in which it is compressed up to a pressure of 225 pounds to the square inch. This displaces the water, forcing it back into the elevated tank and leaving only the tension due to its hydrostatic column of 32 feet.

Glass gauges exactly like those used on steam boilers show the level of the water in the stationary cylinders, and thus enable the attendant to regulate the supply of Communicated by Professor Morton. From advance-sheets of the Journal of the Franklin Institute.

THE RISE AND FALL OF THE DEFUNCT ELEMENTS.*

By Dr. H. CARRINGTON BOLTON.

A COMPLETE catalogue of so-called "Defunct Elements," is nowhere found, but notices of their rise and fall are scattered throughout periodical literature; from these the following list has been compiled, which, if incomplete, is still comparatively full. Within the limits of this abstract, little more than the date, name of discoverer, and references can be given. Taking them up in chronological order, the first is

Terra Nobilis, discovered in 1777, by Tobern Bergmann, who extracted it from diamonds.

Hydrosiderum, discovered by Meyer, in 1780, and obtained by dissolving crude iron in acids, the residue being the new element. It is called in German Wassereisen. Klaproth showed that it consisted of iron combined with phosphorus. (Schrift. Ges. Nat. Freund, Berlin, ii., 334 ; and iii., 380.)

Saturnum, discovered in 1784, by Monnet. (Journal de Physique, xxviii.)

Diamanthspatherde, discovered in 1788, by Klaproth, in corundum. (Beschäft. Ges. Nat. Freunde, Berlin, viii., St. 4.)

*From the Proceedings of the Lyceum of Natural History, New

York.

manner.

By W. GOULD LEISON.

PROFESSOR GIBBS has recently called attention to the fact that a number of metallic oxides may be completely precipitated from their neutral solutions by means of oxalic acid, provided that a large excess of alcohol be also added. As it is not easy to obtain precise quantitative results by igniting the oxalates so precipitated, in consequence of the extreme subdivision of the resulting oxides, Professor Gibbs suggested the employment of potassic hypermanganate for the combustion of the oxalic acida method which, as is well known, gives excellent results in the case of calcic oxalate precipitated in the ordinary The following investigation was undertaken for the purpose of testing this method of analysis :Cadmium.-Cadmic sulphate was dissolved in the least possible quantity of water, oxalic acid added in excess, and then a large quantity of strong alcohol. The resulting oxalate was beautifully crystalline, and the precipitation was so complete that SH2 gave, in the filtrate, a scarcely perceptible yellowish tinge. The oxalate was washed with alcohol by Bunsen's method, and dried at 110° C., until every trace of alcohol was expelled. The filter was then pierced with a glass rod, and the cadmic oxalate washed into a flask with hot diluted sulphuric acid. A few cubic centimetres of strong sulphuric acid were then added, and the hot solution titrated with potassic hypermanganate. In this manner, four experiments gave 44 19 per cent, 4465 per cent, 44.88 per cent, and 44 27 per cent of cadmium, as computed from the oxalic acid. These results are all much too high, and show that the acid had acted sensibly upon the filter. Two other experiments were then made. In the first, a hot solution of ammonic sulphate was used as a solvent for the oxalate; in the second, hot dilute chlorhydric acid was employed. Of the hypermanganic solution employed, 100 c.c. contained o'1103 gr. of available oxygen.

I. 0'4330 gr. cadmic sulphate required 24'5 c.c. hypermanganate=43 68 per cent Cd.

II. 0'3724 gr. cadmic sulphate required 21'1 c.c. hypermanganate=43'74 per cent Cd.

The received formula, 3CdSO4+8H2O, requires 43'75 per cent. In these two analyses the filters were not broken. Barium.-Baric chloride gave extremely variable results in my first experiment, notwithstanding the fact that the barium is completely precipitated by oxalic acid and alcohol. The resulting oxalate, after washing and drying, was not completely decomposed by sulphuric acid, which appeared to form a crust of baric sulphate upon the crystals of the oxalate. This difficulty was finally overcome by dissolving the baric oxalate in chlorhydric acid and diluting the solution largely. In this manner06505 gr. baric chloride required 80 c.c. hypermanganate 56 21 per cent Ba (100 c.c. hypermanganate solution contained o'053 gr. available oxygen). The formula BaCl2+2H2O requires 56.15 per cent Ba. Strontium.-To avoid the use of paper filters, so as to be able to employ sulphuric acid as a solvent, I resorted to sand filters. A light funnel was ground truly conical near the throat; a little pear of glass with a long stem was then dropped into the funnel, stem upward. In this manner, a valve was formed impassable to the sand laid upon the ball of the glass, but allowing liquids to pass freely. By means of the stem, the valve could be lifted

Amer. Journ. Sci., vol. xliv., p. 213.

nate=48.90 per cent SrO.

0'3657 gr. strontic nitrate required 408 c.c. hypermanganate 48.90 per cent SrO. (100 c.c. hypermanganate solution contained o'1099 gr. available oxygen.)

The formula Sr(NO3)2 requires 48.93 per cent SrO. Sulphuric acid only was used to decompose the oxalate.

Calcium.-Iceland spar was dissolved in chlorhydric acid, and the solution treated with oxalic acid and alcohol. The filtrate contained calcium. When, however, the solution was evaporated to dryness before adding alcohol, and the oxalate was washed on a sand filter, no traces of calcium could be detected in the filtrate. In this manner

per cent CaO.

0'5090 gr. CaCO3 required 70.6 c.c. hypermanganate=56·10 (100 c.c. hypermanganate corresponded to o'11559 gr. oxygen.) 0'5590 gr. CaCO3 required 77'5 c.c. hypermanganate = 56'08 per cent CaO. (100 c.c. hypermanganate corresponded to o'11495 gr. oxygen.)

The formula requires 56.00 per cent CaO. Sulphuric acid only was employed.

oxalic acid, the mixture evaporated (but not to dryness), Magnesium. When magnesic sulphate is treated with and alcohol added, the filtrate is perfectly free from magnesium. In this manner

03243 gr. MgSO4+7H2O required 39'6 c.c. hypermanganate 16 18 per cent MgO. 03949 gr. MgSO4+7H2O required 484 c.c. hypermanganate 16.25 per cent MgO.

filter, and washed into the flask with water after piercing In these analyses, the oxalate was collected on a paper the filter, which was washed with cold dilute sulphuric acid. The formula requires 16.26 per cent.

Zinc.-Zinc is completely thrown down from its sulphate by the unmodified process. The oxalate forms an extremely fine powder. A sand filter and warm dilute sulphuric acid were employed.

09301 gr. sulphate required 47'1 c.c. hypermanganate 28.14 per cent ZnO. 1'0788 grs. sulphate required 54'6 c.c. hypermanganate 28.15 per cent ZnO.

The formula requires 28.22 per cent ZnO.

Cobalt.-Perfectly pure anhydrous cobaltous chloride was prepared by igniting chloride of purpureo-cobalt. The chloride was then precipitated by oxalic acid and alcohol, collected on a sand filter, and digested with dilute sulphuric acid. The solution was intensely red. A solution of nickeliferous sulphate was then added, until the red In this mannercolour disappeared and a faint smoky hue took its place.*

0'4292 gr. CoCl2 required 47.8 c.c. hypermanganate=45'30 per cent Co.

0'3657 gr. CoCl2 required 40'8 c.c. hypermanganate=45'37 per cent Co.

The formula requires 45'38 per cent (Co=59).

Nickel.-In the case of nickeliferous sulphate, it was found necessary, after adding the oxalic acid, to concentrate the mixture on a water-bath before adding alcohol, and then further digest for about half an hour, replacing the alcohol as fast as it evaporated. The oxalate was collected on a paper filter, and, after washing, dissolved in ammonia on the filter. The filtrate was then acidified

Compare, as regards this method, W. Gibbs, Amer. Journ. Sci., vol. xiv., p. 204.