Dec. 4, 1891.

(Rhus copalinum) contains rather less tannin than Rhus
glabra. Both the above species of sumac are of American
origin. Chinese sumac (Rhus semialata) is the bark of
a tree upon which the Chinese gall-nuts are produced.
Fustet or scotano is the wood of Rhus cotinus (known in
The best quality comes from
England as young fustic).
Greece and the Ionian Islands. Sumac of Tezera, or of
Africa (Rhus pentaphylla): a grey bark used in the north
of Africa for dyeing and tanning. Egyptian sumac
(Rhus oniyacantha) grows in Egypt and Asia Minor. The
Rhus lucida,
bark of the root is employed in tanning.
shining-leaved sumac, Rhus thunbergi, Řhus levigata and
viminalis are produced at the Cape. Rhus rhodanthema
(Queensland sumac) and Rhus elegans (also from Australia)
are used in dyeing and tanning.

Experimental Researches on the Electrolytic Preparation of Sodium and Aluminium.-A. J. Rogers.(From the CHEMICAL NEWS).

Metallurgical Use of Aluminium and Ferroaluminium (Dingler's Polyt. Journal).-G. Arth.-An account of the use of aluminium in increasing the fluidity Its addition of melted iron and preventing blow-holes. to the melted iron in the converter cannot be recom. A ro-ton mended on account of the increased expense. Bessemer charge with an addition of o'1 per cent aluminium will come to 956 francs.

Working Aluminium.-From the Scientific American. The Properties of Aluminium.-A. E. Hunt, J. W. Langley, and C. M. Hall.-From the Journal of Chemical Industry.

Tempering and Hardening Steel for Cannon and Projectiles.-Prof. Watson Smith.-From the Journ. Soc. Chem. Industry.

On Double Explosions in Puddling Furnaces.— Haedicke (Stahl and Eisen).—The author considers that the first of these twin explosions is due to the sudden evaporation of a large quantity of water in consequence of the cessation of the spheroidal state. This first explosion is followed by a partial vacuum in the interior a simultaneous of the apparatus, when there ensues aspiration of air, and of the combustible gases of the This furnace,-carbon monoxide and hydrocarbons. detonating mixture is ignited in contact with the hot walls of the furnace and causes the second explosion.

Practical Researches on Zincing.-B. Preu (Chem. Zeitung). Of three known methods the author prefers one in which the bath is composed simply of zinc, covered entirely or in part with a layer which prevents oxidation. Sal-ammoniac gives the best results, but it evaporates rapidly and has to be renewed frequently. It diminishes the dangers of explosion, but it occasions unpleasant vapours.

Glass and Ceramic Art.-Under this head come accounts of Japanese enamels (Chemiker Zeitung), photographic process for decorations in relief (Sprechsaal), manufacture of marbled glass (Sprechsaal), yellow lining glass, by Hananeck (Sprechsaal), new red glass (Scientific American), enamels free from lead (Chemiker Zeitung).

On Horse-Fat.-L. Lenz (Chemiker Zeitung).-Fresh horse-fat, if melted in the water-bath, is yellow and neutral; it has the consistence of butter, and after a few days it becomes viscid. Its weight remains constant for four weeks, then gained o 691 grm. in the first year and 0'201 in the second, after which its weight remained constant. The original weight of the sample was 22'521 grms.

Oxidation of Gallic Acid, of Tannin, and of the Tannic Acids of the Oak.-Dr. C. Böttinger. The author on studying the action of nitric acid upon tannin and gallic acid, obtained along with oxalic acid a smaller quantity of two other acids, which may be separated by means of their calcium salts.

Bulletin de la Société Chimique de Paris. Series 3, Vol. vi., Nos. 4 and 5, September 5, 1891.

On Azothydric Acid.-E. Noelting and E. Grandmougin.-According to the researches of Curtius, diazobenzolimide may be considered as the phenylic ether of azohydric acid. This derivative may easily be prepared Under by diazotising dinitraniline, transforming it into perbromide, and treating the latter with ammonia. the influence of alcoholic potassa it is split up very sharply, yielding potassium salts of dinitrophenol and azothydric acid. On acidifying and distilling there passes over an aqueous solution of azothydric acid, which is identified by means of the characteristic reactions described by Curtius. The authors intend to study the other nitrised diazobenzolimides, and to ascertain the most favourable conditions for the preparation of azothydric acid.

Boron Selenide.-Paul Sabatier.-The author obtains boron selenide by passing a current of very dry hydrogen selenide over amorphous boron, kept at a red heat in a tube of Bohemian glass. The boron is entirely transformed into a yellowish grey selenide, showing no trace of fusion. Beyond the "boat" the sides of the tube are lined with a thin powdery layer of pale yellow boron selenide; further on there are found small drops of vitreous selenium, then of scarlet selenium mixed with a little selenide. The sublimate of yellow selenide is briskly destroyed by water, yielding boric acid and hydrogen selenide. The composition of the selenide is B2Se3. A sub-selenide has also been obtained, Bo4Se. selenide is much less volatile than boron sulphide and even than selenium.

Boric

Silicon Selenide.-Paul Sabatier.-This compound was obtained by heating crystalline silicon to redness in a current of dry hydrogen selenide. The conversion takes The selenide takes the place without incandescence. form of a melted, hard, incandescent body of a metallic appearance, which does not appear volatile at the temperature of the experiment. Its composition is SiSea. Water acts upon it briskly, yielding silica and hydrogen

selenide.

Action of Ammonia upon Mercury Cyanide and its Compounds with Haloid Salts.-Raoul Varet.This paper has been already noticed.

Researches on Lead Chromate.-MM. Lachaud

and Lepierre.-Also previously noticed.

Researches on Thallium.-M. Lachaud and C. Lepierre.-The authors describe a series of experiments on thallium chromate prepared by precipitating pure thallous sulphate with neutral potassium chromate. The salt obtained, Tl2CrO4, is amorphous and of a lemonyellow colour. It was treated successively with dilute a state of potassa, concentrated potassa, potassa in fusion, and potassium nitrate. They have also obtained thallium chlorochromate, but not in a state of perfect purity. Reference is made to a new method of determining thallium which is to furnish the subject of future

communication.

Determination of Chrome Yellows.-The method

proposed by the authors will be given in full.

Molecular Lowering of Phenol.-MM. Juillard and Curchod.-The authors find that the molecular lowering of synthetic phenol, fusible at 41.2°, varies with the nature of the substance dissolved. The mean value is 68'5 for water, ẞ-naphthol, paratoluidine, aniline, nitrobenzene, phthalic anhydride, diphenic anhydride, a-naphthylamine, amylic alcohol, vicinic acid, and anhydrobenzhydrolcarbonic acid.

For the neutral ethers, especially the ethers of the bibasic acids, the mean is 75.81. The value 68.5 is the most general experimental lowering, and must consequently be adapted for cryoscopic experiments made with phenol.

bluish one by acids which are desulphonised but poly- The Principles of Chemistry.

Ir the precipitate obtained by adding ammonia to a hydrochloric acid solution of tri-calcium phosphate be dissolved in acetic acid, and the solution kept for some days, crystals begin to deposit and continue to do so for some time.

Having obtained about 2 grms. of these crystals, I washed them thoroughly with water and then dried them in vacuo over sulphuric acid for about four days. They then appeared as brightly glittering prismatic crystals. On heating them in the water-oven for several hours they only lost weight to a very slight extent (0.85 per cent), and prolonged heating to a bright redness in the muffle was necessary before they ceased to lose weight. Analysis of the crystals as dried over sulphuric acid gave the following result:

From this the formula CaH,PO6 is calculated. A substance having the same percentage composition is described by Groves as being formed when Na2HPO4 is added, drop by drop, to an excess of CaCl2, but its properties, as described by him, differ from those of the compound prepared as above.

observed or experimentally demonstrated as the funda

mental functions of protoplasm; but not the sixth--the

chemical action of mass.

On the basis of his experiments on the dead space in chemical reactions, Liebreich concludes that "the occur. rence of every chemical reaction is possible only in excess of a certain definite magnitude of the space in which it is to ensue." It cannot be denied that in capillary spaces the physical influence of the enclosing sides and the various tension of the liquid surfaces are magnitudes which must be carefully taken into account. Almost all capillary reactions, as it is well known, are exceedingly sensitive. It has long ago been decided that these values, which may be neglected under ordinary circumstances, are very considerably modified on quite minute alterations of spacial relations, of the surface of the sides, the physical properties of the liquids concerned, and on the slightest impurities or admixtures; as also on very trifling modifications of temperature, or illumination, &c. Hence it is intelligible that in such variations, which seem quite insignificant for the conditions of the laboratory, important alterations must ensue in capillary reactions. Hence the exact repetition of such experiments becomes an exceed. ingly difficult problem. Even an exact statement of the conditions of an experiment is often almost impossible.

In consequence of this conclusion an ordinary chemical reaction can scarcely be imagined in a microscopic testtube, in a microscopic retort, or in a microscopic flask. Liebreich says very briefly that "a certain size" of the cell spaces is needed if a quite different, and in a manner degenerate, chemical process is not to ensue.

What is to some extent a degenerate chemical process is not intelligible, but in any case our assumption, which agrees perfectly with the first words, appears admissible, namely, that in microscopical protoplasm there are always spaces where a chemical action of mass does not reach validity in opposition to very strong physical influences, though nevertheless intense chemical reactions take place. But where there is no chemical action of mass in protoplasm, the effort towards chemical equilibrium cannot be present. The important formula of Guldberg and Waage

-which is not only inductively derived by experiment, but also deductively from the mechanical theory of heat, does not then hold good for the specific chemism of protoplasm.

From the fact that there is practically no loss of water-kip1q1 = kapagi, the law of the chemical action of mass when heated to 100° C., and, further, that there is no definite temperature at which two molecules of water are lost, together with the fact that a large proportion of the loss occurs only at a very high temperature, it seems probable that the compound does not contain water of crystallisation. If this be so it seems as though the compound were a derivative of the maximum hydroxide of phosphorus P(OH)5. If we suppose this to react with the hydroxide of calcium, Ca(OH)2, and one molecule of water to be lost we get

This law may be most briefly expressed as follows:bases, and q1 and q2 the quantities of the two salts formed If p1 and p2 signify the relative quantities of the free in molecular weights, and k, and k2 constants depending on the mutual affinities of the bases and the salts to each other, the energy with which the two antagonistic reactions tend to be effected may be expressed by kipiq2 and k2p2qi. The main law of the chemical action of mass is then expressed by the formula kiqi1q2= k2p291,—that is, each of the two antagonistic reactions tend to be carried out with an intensity proportional to the relative quantity of the matters concerned or to the number of their mols., and equilibrium is reached at that proportion of quantities at which the opposing forces become equally great.

That this law cannot hold good for living protoplasm follows from the microscopic smallness of the protoplasmic tissues, which display the most in ense metabolism, and the unparalleled variability of protoplasmic matter.

However different are the opinions of the best observers as regards the nature of protoplasm, all, doubtless, agree that protoplasm, whether it is found in the Amoeba living freely in the water, or in the Leucocytes circulating in the plasma of the blood in the sluggish corpuscules of conjunctive tissue, or in the briskly moving cholera bacillus, or in the nucleus of an ovum, in a ganglionic globule, or in a glandular cell, is extremely complicated, and not, as was formerly supposed, homogeneous; not a mucoid, an albumenoid, nor indeed a matter of whatever kind, but that it is exactly characterised by its changes of material, of forces, and of form.

Protoplasm is no chemical compound (to aim at proving this would, in our day, be mere trifling); it is also no simple mixture of chemical compounds as long as it breathes, assimilates, moves, and developes; for we do not call a working machine a simple mixture of the combinations or elements of which it is constructed, or which it takes in and gives out. It is also no mixture of chemical compounds, for we easily recognise for the most part in protoplasm heterogeneous parts, independent of the nucleus of the vacuole, and of differentiated appended structures. It is altogether no structure which, on mechanical or ultimate analysis, yields constant relative quantities of the substances which pre-exist in it, or which may be obtained from it, carbon, nitrogen, hydrogen, phosphorus, sulphur, calcium, &c., but it has an inconstant composition.

WHEN I grm. of scraped meat was placed in a flask and covered with 20 c.c. of a I per cent solution of sodium azoimide, it remained unchanged, and did not putrefy even if infected with schizomycetes. In a check flask, offensive putrefaction set in after twenty-four hours, effected by a multitude of bacteria in brisk movement.

4. Experiments with Hyphomycetes.

To 50 c.c. of a cultivation liquid of the same composition as that used in the experiments with bacteria, there was added, beside I part per 1000 sodium azoimide, 2 parts per 1000 mono-potassium phosphate, and the liquid was then infected with the spores of Penicillium and Aspergillus. But even after some weeks not a trace of the mycelium of mould was developed, even if diammonium phosphate was present in addition to sodium azoimide.

Another nutrient solution, which instead of a tartrate contained 5 parts per 1000 of glucose, and also o'5 per 1000 of sodium azoamide, developed even after many weeks not a trace of the filaments of mould, in spite of infection and exposure to the air. A check specimen, which contained nitrogen in the form of 0'5 per 1000 ammonium chloride, developed on the third day a thin film of mould along with a bacterial turbidity, and on the eighth day a considerable layer of mould.

5. Experiment with Saccharomycetes.

A portion of pressed yeast of the size of a pea was shaken up with 10 c.c. of water; one half of the liquid was mixed with 5 parts per 1000 of sodium azoimide, and the other was let stand for two days without this addition. The latter portion had already an offensive smell, and the supernatant liquid contained numerous bacilli; the former was inodorous and free from bacilli. The ! yeast which had settled to the bottom was brought in contact in a narrow tube with about 5 c.c. solution of glucose. In both cases fermentation was set up in about 25-30 minutes, though less briskly in the portion which had been treated with sodium azoimide.

Saccharomycetes are, therefore, more resistent than schizomycetes and hypomycetes, as has been already shown in many other cases. Whether the poison here penetrates less readily or whether protective arrangements exist in the protoplasm remains for the present, undecided.

6. Experiments with Infusoria.

In

is brought in contact with infusoria under the micro-
scope, there is a sudden cessation of all vital movements.
A o' per cent solution in spring water does not cause
the movements to cease in less than 2-2 hours.
the Vorticella there sets in firstly partial paralysis, when
the stem and the cilia become rigid. In Stylomychia the
movements become for a short time very violent before
they cease altogether. Other Infusoria contract to motion.
less globules, whilst the Euglenæ twist backwards and
forwards for some time before life ceases. If, accident-
ally, species of Cyclops (belonging to the Crustacea) are
found among the infusoria, their rapid movements are
quickly paralysed until life is entirely extinguished.
If the solution is diluted with 10 parts of water, living
Vorticella and Amœbæ may be observed even after twelve
days.

7. Experiments on Various Aquatic Animals.

In a o'5 per mille solution of sodium azoimide in well water, Nematodes, Planariæ, Ostracoda, Copepods, wood lice, small insect larvæ, and young snails (Planorbis, Limnæa) die in 30-40 minutes. In 2-3 hours small water-beetles die; leeches later.

In a o'r per 1000 solution Crustaceans die in 20-24 hours, death being preceded by paralysis. Water-beetles and snails die after four days; leeches and insect larvæ were still living after six days.

8. Experiments on Mammalia.

Prof. Emmerich, of the Hygienic Institute, here kindly made a few experiments, and reports as follows:

"Your conjecture concerning the action of sodium azoimide is fully confirmed. The subcutaneous injection of I c.c. of the I per cent solution caused in a large mouse in ten seconds sudden cramps, emprosthotonus, and instant death. Even O'I c.c. injected into a mouse subcutaneously occasioned in three minutes cramp of the diaphragm, and within four minutes paralysis of the extremities. In two minutes more there set in clonic cramps of all the muscles, emprosthotonus, and death. On the immediate opening of the thorax, the auricles contracted a few times, and the heart then became still. The blood was very dark."

(To be continued).

DETERMINATION OF SMALL QUANTITIES
OF ALKALI AND RECOGNITION
OF THE NEUTRALITY OF WATER.
By F. MYLIUS and F. FOERSTER.
(Concluded from p. 277).

THE figures signify thousandths of a m.grm., and show that the factor ascertained for soda is sufficiently accurate for potassa and ammonia. From all this it follows that our colorimetric method suffices to determine even o'005 alkali with some accuracy.

For the appreciation of the colorimetric method as well as for that of titration with mille-normal solutions, we require a knowledge of the influence of carbonic acid upon the determination of very small quantities of alkali, the more so as our experiments for the determination of the empirical fact r above mentioned were made with a solution of sodium carbonate instead of with one of pure sodium hydroxide. "Neutral" water was therefore saturated with carbonic acid obtained by heating sodium bicarbonate. A saturated solution of carbonic acid contains about o'g grm. carbonic acid per litre. This solution was mixed in various proportions with neutral water, and known quantities of soda were added to the mixture. The

If a drop of a 1 per cent solution of sodium azoimide red colour obtained in the solutions of alkali thus obtained,

* Ber. Deutsch. Chem. Gesell.

after shaking out with ethereal solution of eosine and with aqueous ether, was determined. The results were as

The colorimetric method for the determination of alkali permits by reason of its great sensitiveness a determina-fifteen periodicals devoted to sugar, and omits exactly tion of the quantities of alkali extracted by aqueous liquids from glass vessels in which they have been kept. We) mention a series of experiments in order to show the changes which water undergoes when kept in a glass bottle. The bottle held about 1 litre, and consisted of good glass; it had been well rinsed out with water before the experiments. When neutral water was kept in it for some time, successive portions of the water of 100 c.c. each showed the following values :