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| acid ? Second, can selenium replace sulphur as a consti. tuent of albuminous bodies? If it were possible through the agency of the organs of plants to effect the replace.

ment of an element not merely in an organic, but in an VOL. XXXIX. No. 1019.

organised body, the achievement would be one of the greatest importance. Absolutely nothing has been done in the way of effecting the synthesis of new bodies by

means of the wonderful combining powers which are NOTE ON THE SPECTRUM OF SODIUM. exerted in the vegetable mechanism.

The difficulty with which compounds of selenium By J. N. LOCKYER, F.R.S.

analogous to the organic bodies containing sulphur are

prepared, and the instability of so many of them, are I HAVE lately been engaged in studying the spectrum of facts which deter one from feeling sanguine as to the possodium under new experimental conditions. In anticipa. sibility of effecting the synthesis of organised selenium tion of a detailed communication I take leave to state bodies by means of plants ; still the attempt is worth that the vapour given off from the metal after slow distil. 'making. Much more hopeful is the chance of replacing lation in a vacuum for some time shows the red and green | sulphuric acid by selenic acid. I am of this opinion from lines without any trace whatever of the yellow one. the results of an experiment which I made several years Hydrogen is given off in large quantities, and at times | ago upon a very small scale, and which I never published thie C line and the red “ structure” are seen alone. After up to the present, every year intending to repeat it upcn this treatment the metal, even when red hot, volatilises

a larger scale. The experinient was as follows:-A sod with great difficulty.

was taken from a field in which a crop of the so-called artificial grasses (which are chiefly leguminous plants, and not grasses at all) was just peeping over ground.

The sod was 2 feet in depth, 3 feet in length, and I foot PRELIMINARY NOTE ON THE ABSORPTION OF wide. It was placed in a box, and one-half of the plants SELENIUM BY PLANTS.*

were watered twice a week with a weak solution of potas

sium selenate (K2SeO4). During four weeks the total By CHARLES A. CAMERON, M.D.,

quantity of potassium" selenate applied to the plants Professor of Chemistry and Hygiene, R.C.S.I.

amounted to 20 grms., which comprised my whole stock

of the article. The subject of the possibility of replacing some of the

Now, this experiment was merely a tentative one.

First, to ascertain whether or not selenic acid would act elements found in plants by other elements of the same

injuriously upon plants. Secondly, to discover whether atomicity has not engaged the attention of British che.

or not the selenic acid could partly replace the sulphuric mists; but on the Continent a few attempts in this direc

acid, or rather could be taken up into and permanently tion have been made, generally with but little success.

retained by the plant. With respect to the action of the For example, Berner and Lucanus vainly attempted to replace ferric oxide (Fe2O3) in plants by the manganese

selenate, I could not perceive any difference between the

plants to which the salt had been applied and those to analogue of that compound (M203). Experiments made

which it had not. I came to the conclusion, therefore, with the view of substituting sodium for potassium in

that selenic acid applied at least in small quantities did plants have invariably given negative results. The possibility of completely replacing an element in plants by

not injure plants.

The next step was to ascertain whether or not the another was, however, proved by me in a paper read before

selenic acid had been partially absorbed. The plants were this Society in 1863. I found that rubidium was capable

accordingly partially dried, and boiled in strong nitric of taking the place of potassium. It may be that certain

acid until thoroughly destroyed. The solution was eva. bodies, though not capable of completely replacing other

porated to dryness, and the residue was treated with substances in vegetables, may be partially substituted

dilute hydrochloric acid, which dissolved it nearly com. therefor. The varying proportions of sodium and potas

pletely. The solution was concentrated and mixed with sium found in the ashes of plants would see n to indicate

a saturated solution of sulphurous acid, whereupon the such a partial replacement. As a rule, whenever potas.

liquid assumed at once a deep blood-red colour, from the sium is sparsely present in the ashes of a plant, sodium

separation of selenium. abounds therein, and vice versa.

Before the plants were partially dried they were care. The analogy between sulphur and selenium suggests the

fully washed, in order to separate any traces of selenate possibility of the latter wholly or partly replacing the

| which might have adhered to their surface. The applicaformer as a constituent of vegetables. Sulphur exists in

tion of the selenate solution was discontinued for a fortplants on two conditions, namely, as a constituent of sul

night before the plants were taken up. phuric acid, and as an ingredient of albuminous and cer

I think this experiment proves that selenic acid is not tain oily bodies. Sulphur is only taken up into the

| injurious to plants when used in small quantity, and that mechanism of plants in the form of sulphates, such as,

the acid is taken up and retained by plants, or at least of for example, calcium and sodium sulphates. By the par

certain varieties of plants. The experiment, however, tial deoxidation of these sulphates, sulphur is procured by

did not prove whether or not there was a partial replace. the plant and employed in the elaboration of its albumen,

ment of sulphur trioxide by selenium trioxide or of sulphur casein, and other albuminoids. The results of the inte

by selenium. Having lately become possessed of large resting experiments of Arendt render it probable that culpbur is both oxidised and deoxidised in the plant at quantities of selenium compounds, I proposed to grow

plants in soil or water free from sulphur in any form, but different periods of its development. Thus, after blossoming the oat was found to contain more sulphur trioxide supplied with potassium and ammonia selenates. Should

the results of this proposed experiment prove interesting than before the ears of the plant had formed; and whilst

I shall do myself the honour of submitting them to the the sulphur trioxide disappeared altogether from the lower part of the stem, it increased largely in the leaves and in

Society. the plant at large.

Now, there are two problems to be solved in relation to the substitution of selenium for sulphur in plants. First,

Proportion of Carbonic Acid in the Atmosphere.

|--J. Reiset.—The air contains in to,ooo parts 2'942 parts can selenium in the form of selenic acid replace sulphuric

of carbonic acid by volume. The most extreme variations * Paper read before the Royal Dublin Society, May 19, 1879. I have not exceeded 3 parts in 10,000.-Comptes Rendus:





Composition of the Ash of Wheat-Bran.


1 June 6, 1879. ON AURIN.* Part II.

| The material had the appearance of having been comBy R. S. DALE, B.A., and C. SCHORLEMMER, F.R.S. | pletely fused, and was very free from even minute specks

of either charcoal or sand. It had a specific gravity of

2-34, and a hardness of 3'5 to 4. Some time ago we read a paper before this Society, in

The analysis gave the following results :which we stated that on heating aurin, C19H1403, with an excess of aqueous ammonia, it is converted into para

Per cent. rosanilin, C19H17N3.7 There ought to exist two com

Chlorine .. .. .. .. .. .. 0:612 pounds standing intermediate between aurin and rosanilin, Sulphuric oxide (S03) .. .. .. 0'151 viz., C19H15NO2 and C19H16N20, as the action of ammo

Silicic , (SiO2) .. .. .. nia probably proceeds in three stages :

Phosphoric , (P205) .. .. .. 48.328

C19H403+NHz =C19H15NO2+H20,

1 (K20) ..


1: Na2O).. .. .. Calcium

(CaO) .. C19H6N2O+NH2=C19H19N3+H2O.

. 10615

Magnesium, (Mg).. .. 18.980 We have made a very large number of experiments for

Ferric , (Fe2O3).. .. .. 2°015 the purpose to get hold of one of these intermediate pro

Water .. .. .. .. .. .. ..

0*438 ducts, and have at last succeeded in obtaining one, probably

Sand .. .. .. .. .. .. .. 3:170 the first, in beautiful crystals; it dyes on silk and wool a rich red, and as the commercial red aurin, which is ob.

98.259 tained by the action of ammonia on common or yellow aurin, has also been called peonin, we will retain this Which may be interpreted as indicating the following name for our compound. It is formed by heating aurin composition for the ash :with dilute ammonia to 100° C. for some weeks. A body

Per cent. dyeing exactly the same shade, and therefore undoubtedly Potassium chloride (KC) .. .. 1*2887 the same compound, is obtained by passing for a few

silicate (K,SiO2).. .. 2-5936 hours ammonia gas into a solution of aurin in boiling

phosphate (K3PO4) .. 5.8337 amyl alcohol.

Sodium phosphate (NazP04) ... 11°7370 As we encountered many difficulties in the preparation

Hydrogen phosphate (H3PO4) .. 9*3721 of peonin, we thought more definite results might be ob.

Calcium sulphate (CaSO4) .. .. 1'9567 tained by using a compound ammonia, and therefore tried

phosphate (Caz(PO4)2) .. 18:2342 the action of methylamin on aurin. Methylamin is now

Magnesium phosphate (Mg3(PO4)2) 41'4600 a commercial article, being obtained from beetroot

Ferric phosphate (Fe2P208) .. .. 3.8058 molasses by M. Vincent's method, which Dr. Roscoe

Water, hygroscopic (H20) .... 094379 described to this Society some weeks ago; he was kind Sand, insoluble residue.. .. .. 3*1700 enough to present it with the methylamin required for our experiments.

99.8897 On heating the two bodies together for a few hours, the deep red colour of the liquid became much paler, and a The remarkably large percentage of phosphoric oxide brown deposit was formed in the tubes, which on exami- | present at once attracted my attention, and at my sug. nation was found to be trimethyl-para-rosanilin, which is gestion the determination was repeated. The results of formed according to the equation

the four determinations made with uranium acetate were C19H1403+3(CH3)NH2=C19H14(CH3)3N3+3H20.

very closely concordant, and I think of unimpeachable

accuracy. We have dyed with it, as well as with the other bodies

No carbonic oxide (CO2) was present. The very small mentioned in this paper, silk, wool, and mordanted cotton,

proportion of chlorine is doubtless due to the high temand beg to submit these samples to your inspection.

perature to which the ash had been subjected-a temperWe have already proved that by acting on aurin with

ature sufficiently high to coinpletely fuse it. The substance aniline the final product consists of triphenyl-para

may therefore properly be considered an ash residue con. rosanilin, and thus shown that the whole host of bodies

sisting of its less volatile portions. The presence of free known as the aniline colours can be obtained from

phosphoric acid in such a compound may be questioned; phenol.

perhaps also the presence of normal magnesium phos. phate. It must be remembered, however, that it is

scarcely a supposable case that the phosphates in the bran ON THE

are acid phosphates, producing pyrophosphates when COMPOSITION OF THE ASHES OF WHEAT. burned; and while it would appear more probable that the BRAN, BURNED UNDER A STEAM-BOILER.

albuminoid phosphorus contained in the bran would burn

into phosphoric oxide and escape in the smoke, it is not By S. F. PECKHAM.

a necessary supposition, especially when the results of

analysis show that there is more phosphoric oxide present Some time ago, at a meeting of the Minnesota Academy

than is sufficient to form normal phosphates with the of Natural Sciences, a substance was handed me by

available bases. I have therefore assigned the composi. someone present with the remark that it was the fused

tion given above as the most satisfactory interpretation of ashes of wheat-bran, burned under a steam-boiler. The

the results. material was nearly pure white in colour and vesicular in Laboratory of the University of Minnesota, structure, resembling more nearly some specimens of

May 7, 1879. Cooper River phosphate than anything else that I re. member. Wishing to learn its composition I submitted it for analysis to Miss Cora J. Brown, then a student in Heat attending the Formation of Cyanogen.-M. the University Laboratory. Miss Brown had already Berthelot. The mean heat evolved on the combustion of proved herself a very careful and skilful manipulator, and

cyanogen, calculated for its equivalent C2N=26, is she conducted the analysis with exquisite neatness and

132'3 calories. In its formation heat is absorbed to the patience, and with the most gratifying results.

extent of 383 cals. Hence, like acetylen and nitric Paper read before the Manchester Literary and Philosophical

oxide, substances which play the part of true con pound Society, Aprili, 1879.

radicals, it is a body formed with disappearance of beat. Mem. Lit Phil. Soc. (3), vi., 248,

|--Comptes Rendus.

NOTE ON THE DETECTION OF SOME identification of these complex bodies; and it occurred to RARE METALS IN PYRITES FLUE DUST.

me that possibly they might give Weselsky's reaction in

| their unaltered condition. To test the matter, I mixed By DAVID PLAYFAIR,

in test-tubes 5 c.c. water, I c.c. of a saturated solution of Assistant in St. Rollox Laboratory, Glasgow.

nitrate of aniline (probably containing toluydin), and I c.c.

of very dilute solution of potassic nitrite, and added to The Aue dust which was examined was taken from a short each tube 1 c.c. of solutions containing as nearly as Aue leading from pyrites kilns in which Spanish cuprous possible 5 grms. per litre of the following bodies :-(See pyrites were burned. As the flue in question was an iron tube | Table, next page.) not more than 2 or 3 yards long, anything that condensed In five minutes most had become yellow, gambier, and in it must have done so at a very high temperature ; and oak, and churco barks deeply so, and in an hour oak and that probably accounts for the very small quantity of se. | churco barks had deposited a deep red precipitate. In lenium found, as that metalloid is found in appreciable twelve hours all had precipitated more or less, but the quantities in the sulphuric acid manufactured from these glucose and sugar yielded only traces. The gambier, pyrites.

which contains catechin, a well known phloroglucide, The greater part of the flue dust consisted of com. I gave a fine deep red precipitate, and oak and charco barks, pounds of arsenic, antimony, lead, copper, and iron; but which very probably contain phloroglucin, gave precipitates it is only the thallium, tellurium, and selenium that this of which the lower part was equally bright. note is concerned with.

It seems evident, therefore, that phloroglucides in comThalliuin.-The flue dust was treated with sulphuric bination may yield this reaction, but that many other acid for the extraction of the thallium, which was preci. bodies also give reddish-brown precipitates which may pitated as chloride. The chloride was re-dissolved and easily lead to mistaken conclusions. When more dilute re-precipitated twice, and then reduced to the metallic solutions are used the same facts are observed, but the state with cyanide of potassium. One sample of fluered precipitate is more distinct from the rest. Some precipi. dust, treated thus, gave about 0.05 per cent of thallium, tate was even obtained on long standing from aniline while in another case the amount obtained did not nitrate and potassic nitrite alone. The precipitates seem exceed 0'002 per cent.

remarkably stable, being unaltered by solution of iodide, Tellurium. --The insoluble matter left after the above dilute acids, ammonia, sulphurous acid, or sulphide of treatment with sulphuric acid was boiled in a solution of sodium. caustic soda. The solution was filtered off, acidified with The yellow supernatant liquid, if acidified and exposed hydrochloric acid, boiled, cooled, saturated with sul. to the air, becomes bright crimson, and sometimes de. phurous acid, and boiled again, when the selenium and posits minute crimson double-refracting acicular crystals. tellurium were precipitated. This precipitate was col. It is turned yellow by ammonia and its colour restored by lected, dried, and then fused with cyanide of potassium in acids. an atmosphere of coal-gas. The fused mass was allowed Watts states that pyrocatechin gives Weselsky's reto cool, and then dissolved in warm water saturated with action. coal.gas, and through which a stream of coal-gas was! The churco bark to which I have alluded is the product kept continually passing, on a filter. The telluride of of the Oxalis gigantea of Chili, and contains a red tannin potassium thus dissolved passed through the filter exhi. equal in amount, by Löwenthal's test, to from 25 to 26 biting its characteristic claret colour, which it, however, per cent. quercitannic acid. The sample in my possesimmediately lost, becoming colourless, and precipitating sion was kindly supplied by Messrs. Machado, of Glasgow. tellurium unless a stream of coal-gas was kept passing I have made some preliminary experiments as to the through the filtrate also.

application of Wiesner's test for woody fibre-the purple The amount of tellurium found was about o'002 per cent

colouration produced on moistening it with solution of of the matter undissolved by sulphuric acid in the treat. phloroglucin and then with the hydrochloric acid (Chemical ment for thallium. The amount of selenium did not Society's Fournal, 1878, p. 809) to the converse detection exceed o‘oor per cent.

of phloroglucides. Deal shavings moistened with solution of gambier gives it strongly. I hope to pursue the subject | further.


II. Explosive Product of Solution of Phosphorus in By H. R. PROCTER.

Bisulphide of Carbon.

In packing my chemicals for removal to a new labora. 1. Weselsky's Reaction for Phloroglucin.

tory, I came upon two bottles of this solution, probably This readion is described in the Chemical Society's five or six years old, which had formed an orange-yellow Fournal, 1876, i., 964, and consists in the production of a deposit on the sides. Having recently read of a case, to cinnabar-red precipitate when a trace of phloroglucin is which I am sorry that I cannot at the moment reser, added to a solution of nitrate of aniline or toluydin con in which a hottle with a similar deposit had extaining a little nitrite, and the mixture allowed to standploded violently on being broken, I determined to try some hours.

the experiment at once, lest it might try itself under It is known through the researches of Hlasiwetz (Anil. | more dangerous conditions. The bottles were thrown der Chemie, cxliii., 290) and others, that many tannins against a wall, and one exploded with a large puff when heated with dilute sulphuric acid are resolved into of Aame and white smoke: the other gave a slight glucose and peculiar red bodies which we may call phlo. Aash, and smoke which smelt rather of phosphoretted baphenes. These again, when fused with potash, are hydrogen than of phosphoric acid. It is evident that decomposed into protocatechuic acid and another body, some new and spontaneously inflammable compound had which in some cases is a fatty acid, and in others as the been formed, since the fresh solution only inflames after species of sugar known as phloroglucin.

some minutes, when the carbon disulphide has had time To be able to recognise these phloroglucide tannins with to evaporate, and fails to do so at all when the tempera. out the tedious process of separation noted above would ture is very low. In the present case the thermometer was be an important aid to the classification and qualitative below freezing-point, and combustion was instantaneous.

Phosphoretted hydrogen is out of the question, unless * Read before the Chemical Section of the Glasgow Philosophical moisture had found its way into the bottle. Society. 7 Read before the Newcastle-upon-Tyne Chemical Society, March 27,

Of course I can claim no originality irthis observation, " ( but think it well to put it on record as a caution, since




CHEMICAL News, Experiments with the Electric Light. 246

1 June 6, 1879. No.

In Five Minutes.
In One Hour.

After standing over night. 1. Gallic acid .. .. .. .. Yellow colouration Orange, no precipitate Dark red-brown precipitate 2. Gallotannic acid .. .. Ditto

Deep yellow
Orange, turbid

Venetian red precipitate (compaa) 4. Oak bark tannin (50 grms.


Orange, red precipitate Ditto, upper part darker bark per litre).. .. . Pyrogallol .. .. .. .. Pale yellow

Orange, turbid

Reddish brown flocculent ppt. 6. Churco tannin (20 grms. Deep yellow Dark orange, red precipitate Red precipitate, flocculent, dark bark per litre).. .. ..

above 7. Cane-sugar .. .. .. .. Colourless

Clear yellow liquid

Trace brown precipitate 8. Impure glucose .. .. .. Ditto



the reaction might easily give rise to a dangerous their caresully conducted experiments. One great point accident.

which has been decided on the Victoria Embankment is

that the steadiness of the light is in a great measure de. III. Determination of the Free Acid in Tan Liquors. pendent on the regularity with which the motive power is Tan liquors usually contain, in addition to tannins,

supplied to the electric machine. In the present case this gallic acid, catechu, and other bodies of very feeble acid |

| uniformity of power was secured by the use of a specially properties, a certain portion of acetic and other fatty acids,

constructed 20 horse-power engine, provided with an autoand frequently free sulphuric and hydrochloric acids, which

| matic governor of extraordinary sensitiveness, the whole have been purposely added. For technical purposes it is

being supplied gratuitously for three months by Messrs. often desirable to determine these stronger acids, which

Ransomes, Sims, and Head, of Ipswich. are capable of dissolving lime and swelling the tissue of

The experiments upon which Messrs. Basalgette and hide in presence of tannin, &c., which have the opposite

Keales's figures are founded began on January 24th, and effect. This cannot be done by an alkaline solution and

were continued until February 5th, Sundays excepted, litmus, since the tannins are immediately oxidised in

or, in other words, for twelve nights,- the engine being alkaline solution, giving rise to dark coloured products,

driven for 5.5 hours each night, the whole 26 lamps being which obscure the end-reaction.

lighted. The mean daily cost of working the engine, inA simple and sufficiently accurate method for techni.

cluding wages, was found to be fi gs. 81d., or 3.24d. per cal purposes is to use lime-water as the standard solution,

lamp per hour. The cost of the whole plant was £1280, adding it to the clear filtered liquor in a beaker until per

but a smaller engine would be quite sufficient for the pure manent turbidity is produced. This point is easily recog.

| pose; the capital required, therefore, might be reduced nised by holding the beaker over a printed page.

to £990.

The end reaction, of course, depends on the fact that calcic

The accurate estimation of the amount of light given tannates are soluble, or more probably cannot be formed

off by the electric arc and ignited carbons is," say the in the presence of a free and stronger acid. I have not

Reporters, "a matter of great difficulty, so much so that attempted to determine exactly what acids are estimated

the best results which have been obtained can only be by this process, the mixture is complex, and the amount

looked upon as fairly approximating to the truth.” This of lime which they are capable of dissolving is the essen

difficulty arises from two causes : first, from the difference tial point in practice.

in colour between the electric light and any standard of light at our command; and secondly, the fluctuating character of the electric light. The photometrical experiments

made on the Embankment were-ist, on the naked light; REPORT ON THE EXPERIMENTS WITH THE 2ndly, on a light with an opaline globe; and 3rdly, on a

light with a granulated globe. The measurements were ELECTRIC LIGHT

made with an ordinary bar photometer, fitted with a ON THE VICTORIA EMBANKMENT.

movable screen with a star disk.

The standard unit of light which was used was a sperm The joint official report of Sir J. W. Bazalgette, the

oil lamp, specially constructed for the purpose by Mr. Sugg,

and fitted to the photometer by a peculiar balance, by engineer, and Mr. T. W. Keaies, the consulting chemist of the Metropolitan Board of Works, has recently been made

which the necessity for removing the lamp during the public, and is a model of what such a report should be.

course of any number of experiments is obviated. The For the first time in the history of the electric light, as

unit of light given by this lamp was equal to 16 Parliaapplied to street illumination, we have a series of data

| mentary standard sperm candles. Twenty readings were laid before us about whose accuracy there can be no

made on each experiment, both with open and shaded doubt. Hitherto such reports have emanated froni either

lights,-that is to say, 160 on the naked light, 24 with the gas-managers or electricians, whose interests—wrongly

| opaline globe, and 16 with the granulated globe. The we think-have been held to be opposed to each other;

following are the mean results obtained in these experihence the singular discrepancies in the data which have

ments:been issued up to the present time. It must be perfectly

Naked light .. .. 378.1 sperm candles. understood that we in no way intend to make the slightest

Opaline globe .. .. 154'9 , imputation against the honour of the authors of these re Granulated globe .. 265'

01 ports; but when one side tells us that the electric light is The loss of light produced by the opaline globes is 59 per cheaper than gas, and the other that gas is cheaper than cent; by the granulated globes, 2999 per cent. the electric light, we can only account for the discordance | Taking the above data as approximately correct, the of opinion by supposing tnat the reporters' judgment must gross output of light from the twenty Jablochkoff candles have been unconsciously influenced by their anterior con amounts to 7562 candles, nearly 60 per cent of which is victions. In the present instance we have the conclusions absorbed at once by the opal globes. There are also two of two eminent public officials, who have no other interests other sources of loss : first, from the greater thickness of to serve than those of the community at large, and who the opal glass in the lower third of the globes; and are wholly independent of the advocates or opponents of secondly, from the fact that the most favourable direction either system of lighting.

for the projection of the light from the Jablochkoff candle We regret that we cannot follow the reporters through is upwards, there being an actual diminution of light all the elaborate series of calculations which they have horizontally, and still more so downwards. laid before us; we can only gather a few of the results of On the 14th and 15th of March a very important expe

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