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per cent.

Bicarbonate of soda

20:43 24:17

1:31 None 17:07

('ram of tartar.. Starch....

100.00

more, M.

Mott, chemist of the United States Indian De- as follows: 1,000 grains of bread are burnt partment, had occasion to analyze a number down to a small bull, powdered with about of baking powders, and found that many of 100 grain measures of hydric chloride, and them contained alum and other injurious sub- warmed for a few minutes; about two ounces stances. The best baking-powders are, accord- of water are then added, boiled for five mining to Dr. Mott, composed of bitartrate of pot- utes, filtered, etc. A solution containing about ash, tartaric acid, carbonate of ammonia, and 250 grains of pure sodic hydrate is made in a soda bicarbonate, bound together by a little very little water; and to this solution, when starch. Inferior bakiny-powders consist of boiling, is very cautiously added the boiling alum and bicarbonate of soda, and often con acid solution of the charred bread, the whole tain terra alba, insoluble phosphate of lime, etc. boiled for a few minutes, filtered and washed. The physiological effect of alum taken inter- The filtrate, after the addition of a few drops nally is to produce dyspepsia, constipation, of a concentrated solution of disodic phosphate, griping, and a host of other disorders of the ali- is slightly aciditied with hydrie chloride, and mentary tract; and though a person need not subsequently rendered just alkaline with amapprehend that such grave evils will at once monic hydrate and boiled. The precipitate is ensue after eating bread “raised" by such collected, washed, and weighed as aluminic powers, there is no doubt that the protracted phosphate. use of such bread would produce the morbid Vair Elements. Although research appears conditions enumerated. In the tables which to be tending toward a confirmation of the view follow, Dr. Mott states the results of his own that the elements are really compound, and quantitative analysis of different baking-zow- that on further analysis they will be found to ders:

have striking points of resemblance if not acNo. 1.-il Dicking-Poudler mute in Vero York

tual identity, several so-called new ones hare

been added to the list during the year. Burnt alum..

Philippinm was found as an oxide bır Mr. Saquicarbonate ofummonia.

Mari Belafontaine in a specimen of samarskite (an uranoniobate of yttrium and iron) fron Vorth Carolina. The earth of this metal (phi

lippia) is yellow like terbia, but its equivalent 10. 2.—.1 Buking-I’owder muafuctural in Dalli

is lower. In communicating to the Paris Acad

emy of Sciences an account of his discorers, 20:03 per cent.

Mr. Delafontaine takes its approximate equivalent to be comprised between 90 and 95:

Philippie formiate crystallizes with great facility, either on coolin, or by spontaneous evaporation, in small, brilliant, rhomboidal prims, less soluble

than the formiate of yttrin. The terbie forniate is 10. 3.--1 Bukir-Powrider 1.'!muttural in St. an.yurous and soluble in i'rom 50 to 35 parts of waLouis, Jl.

ter. The sodio-terlie sulplute dissolves with diff30:06 per cent. culty in a saturated solution of sodic sulphate, wbile

the corresponding salt dissolves in it easily, .
In the spectroscope the concentrated solution of
philippium gives in the indivo-blue a magnificent al-
sorption band, very intense and rather broad, with

well-cetined edges. This band, which strikes one Vo. 1.-.1 Duki,19-Iowiler manujiuctured in Dil. at a first glance, is not seen in solutions of terbium, wanikir, lis.

vttrium, and crbium. It is, thien, characteristic of 02:3,3 per cent.

philippium, and thus Jl. Soret's conjecture that it belongs to il new simple body is contirmed. In the green are seen two rather fine rays varying in intensity, the most retragible of which belongs to erbium, as well as a faint ray in the blue near to the boun

<lary of the green. The least refrangible of the green Estimation of llum in Bread. The old Vor- rays belongs perhaps to philippiuni ; for, if in some mandy or soda process for the estimation of specimens it has been less intense, others, on the

contrary, show it to be nearly as powerful as the eralumn in bread has long been out of use, on ille bium ray: Lastly, in the real there is at least one count of the great difficulty experienced in time ray which has not been identified, redissolving the aluminie liyerate or phosphate The same chemist reports the discovery of & after its precipitation, which often led to inar- second new element in the same mineral (sacurate results. Other processes have been sub)- marskite), to which he has given the name of stituted, many of which are very complicated decipium. The oxide of decipium (assuming its and unsatisfactory; and they are now likely formula to be IpO) has a molecular weight of to be displaced by a modification of the Vor- 129. The nitrate gives an absorption spectrum mandy method, which simplifies the procedure consisting of at least three bands, in the blue and leaves little to be desired in point of accu and the indige). The most refrangible of them racy. This consists in adding the boiling acid is a little less broad than that of philippium, solution of the charred bread to a boiling solu- is dark, and corresponds in its center to å tion of sodic hydrate, containing a large excess, wave-length near 4,160. This distinguishes

Burnt alum...
Bicarbonate of soda.
Cream of tartar.
Starch....

22.50
None
57 17

100.00

Burnt alum... Bicarbonate of soda. (ream of tartar...

31.92
Nono
3:12

Starch.......

10).0):)

Burnt alun...
Bicirbonate of' sodal.
(rem of tartar.
Starch...

20:19
None
56.03

100.00

decipium from didymium and terbium. The element from thorium, the only element known second band is narrow, intense, not defined on to possess so high an atomic weight. its edges, and is in the less refrangible part of Chemistry of the Grape.In order to test the blue, corresponding to a wave-length of the action of certain special fertilizers on the 4,780. This is nearly the exact place of one of quantity and quality of grapes, Professor C. the didymium bands, but the latter is far less Ā. Goessmann instituted a series of field exintense. Finally, nearly on the limit of the periments with the Concord grape and the blue and green there is an appearance of the wild purple grape (Vitis labrusca, L.), an acthird band.

count of which is published in vol. ii. of the Another new element is announced by Dr. Proceedings of tho American Chemical SoJ. Lawrence Smith, which he calls mosandrum; ciety.” Ilis examination was for the most part this, too, was found in samarskite. The earth contined to the berries and the juice of the (mosandra) of this metal belongs to the cerium grapes. The former were tested for the group.

amount of water they lost at 100° O., and the Finally, Marignac has described some of the total dry matter left behind at that temperacompounds of a new element found in gado- ture. The juice of the grapes, obtained after linite, and to which he gives the name of ytter- crushing in a hand-press, was examined for its bium. The atomic weight of 131 is provision- specific gravity, its percentage of grape sugar, ally adopted for this element. The nitrate is and its frco acid. Ash analyses also were decomposed by heat without coloration; the made, but a detailed discussion of their results oxide is less acted on by acids than the other is withheld by the author for the present. oxides of the same group; and sundry other The following tables show the results of expeculiar reactions serve to distinguish the new periments with grapes not fertilized :

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It will be noticed from the above tabular of the August maximum. The sugar began to statement that with the middle of August be increase at the same time, and continued to gan a remarkable change in the growth of the increase till the fruit was ripe. Concord grape. The free acid became most In tho following table are given the results prominent in the juice about the first week in of observations on various kinds of cultivated August, sank to less than half its quantity to- ripe grapes, all as far as possible collected at ward the close of that month, and amounted the same stage of maturity. Other varieties at the beginning of October to only one fifth not mentioned were also examined :

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The different kinds of grapes above mentioned be- culiar, in all probability, to the wild native varieties haved, in many instances, quite remarkably unlike from which our cultivated ones have been produced. each other in regard to the action of their juice to- This reaction may prove of practical use as an aid in ward basic acetate of lead. The latter producos in tracing tho relationship to cach other of the differovery case a voluminous colored precipitate; yet ent varieties of grapes under cultivation. Dr, G. these colors seem to result from the presence of sev- Engelmann, in his excellent description of the true oral distinctly different pigments in the grapes, pe- American grape-vines, incidentally states that somo

neer's.

growers consider the Delaware and the Clinton as On opening the tap in front of the blast-pipe derived froin the same wild variety, the Riverside this superheated steam passes down the small ful, judying from the reaction with basic acetate of pipe outside the generator, and blows with lead; for the juice of the Delaware grape gives a

considerable force into the blast-pipe, carrycream-colored precipitate, while that of the Clinton ing with it by induction a stream of air. in produces a bluish-green one, indicatiug quite differ- this way the requisite oxygen to support comeut rigmeuts in these varieties.

bustion and steam for decomposition are driven An Economical IIcating G43.—IT hen steam into the apparatus, from which they issue as is passed over coke or charcoal at a red heat, al details of the working of the machine would

To describe fully the severdissociation of the elements of the watery vapor takes place, the hydrogen being set free, require more space than can be afforded here, and the oxygen forming compounds (carbonic but the whole subject will be found treated in oxide and carbonic acid) with the carbon ; extenso in the Journal of the Society of marsh gas is at the same time produced in Arts,"? No. 1325. The chemical reactions which small quantity. The proportion of the gases

occur in the generator are described as follows thus generated is, according to Frankland: by the author of the paper just quoted: II, 56-9; C(), 29•:3; C02, 1:3:8. It is evident Carbonic anhydride (CO2) is doubtless first formed that here we have a l'ery important heating by the action of the oxygen of the air upou the cargas, if it could be produced economically in bon of the fuel; this in its passage upward tbrough

the heated fuel takes up another equivalent of carconsiderable quantities. llow to do this ef- bou, becoming reduced to carbonic oxide, Co, thus, fectually is the problem which has long on

('0), + (= 200), the nitrogen of course passing off gaged tre attention of chemists and gas-engi- unchanged and serving only to dilute the gas. With

This problem woud appear to have respect to the stcam, this, as explained above, is debeen solved a few years ago by Joshua Kidd, composed in its passage over the incandescent coal,

with the formation of hydrogen, carbon monoxide, an English inventor; and the improvements and carbonic anhydride. The latter in its upward which have since been made on his process course shares the same fate as the CO2 produced by justify the belief that a perfectly satisfactory the action of the oxygen of the air, i. c., it takes up solution has been found of the question of a

another atom of (', and passes into the state of co. cheap heating gas fur don:estic and manufac- terially to the calorific value of the gas, by enriching

The decomposition of the steam, therefore, adds maturing purposes.

it with hydrogen and a further quantity of Co. In kidl's system perfected the generator consists of a hollow cylindrical body or case of wrought or

The composition of the gas produced by this cast iron. This is terminated below by a cast-iron generator, when working at different pressures bottom, having a hole in its center about one hall or of water, and with various kinds of fuel, has one third of'its own diameter; below this is a second been determined by analysis. The result is as hollow cylinder of the same internal diameter as the

follows: holo above it; in this lower cylinder the fire-grate is lodged, the blast-pipe opening into it below the firegrate. When making yas, the bottom of the small

Composition per cent by

volume of the gas. cylinder requires to be closed air-tight. This is effected either by means of a flut binged plate, which

Square inch, is kept tightly pressed against it by a beavily weighted lever, or else by a short cap with a beveled edge Peat churcoal...... attached to it by a bayonet joint. In the upper and larger cylinder there is a coil of thick wrought-iron pipe which tits the cylinder pretty closely. The two ends of the coil are turned outward at right angles, und pass gas-tight through the body of the gene erator ; the lower end is connected with an arrange

Anthracite.... ment for supplying water under pressure, and the

(0 = upper end with a smaller steam-pipe passing down parallel to the generator and terminating in a small steam-tap in front of the blast-pipe. In the center of the top of the apparatus is a circular opening nine inchies in diameter, communicating below with a hollow inverto truncated cone projecting into the ga??- Equal parts of anthracite ! s0lbs. erator; at the apex of the cone is a narrow cylindri and steam coal... cal ring, which serves as the sout for a heavy conical valve. Above, this is surmounted by a short cylindrical fuel-box, carrying at its upper end a hopper, the

100-3 opening between them being covered by a sliding plate. Attached to the fuel-box is a short flue used only when lighting the fire. Besides the central open

Anthracite..

60 lbs. ing in the cover, there are two smaller ones, viz., the gus-outlet and a peep- or stoke-hole. If, now, a fire be lighted in the interior of

100.0 this machine, and water driven through the coil, that water will be made to boil; steam As regards the quantity of mixed gases prowill be produced which will accumulate in the duced from a given quantity of fuel, this has upper part of the coil, and, if not immediately been ascertained experimentally with the folallowed to escape, will becomo superheated. lowing results:

DESCRIPTION OF TEL.

Pressure of

water.

!

CO =

28.6 14.6

15 lbs.

II

[ocr errors]

53.0

1002

CO
H

15 lbs,

CII =

92.6 10.0 4-9 4.5 59.0

[ocr errors]

100.0

CO

II
C14
CO2

[ocr errors]

28.3 9.8 5.2 6.2 51.8

[blocks in formation]

DESCRIPTION OF FUEL.

Water-pressure Cubic ft. of gas
in lbs. per sq.in. per Ib. of fuel.

15

69.5 85.2

20

steam coal...

25

88.81

steam coal...

30

94.5

steam coal.. 5. Anthracite

40

2NII:) with excess of ammonium chloride, the metal would be entirely thrown down as a

double chloride. The result, however, was 1. Anthracite...

otherwise; for, instead of the expected com2. Equal parts of anthracite and

pound, they obtained a reddishi-black sub3. Equal parts of anthracite and

stance, Pd2C132NIIs, being a combination of 4. Equal parts of anthracite and

ammonia with a palladiuin chloride hitherto

unknown. (over) 100.0 Nero Process for the Regeneration of Spent

Gas-Lime.-A new process for regenerating It will be seen, therefore, that there is a the foul or spent lime of gas-manufacture steady increase in the quantity of gas produced has been introduced into many gas-works in per pound of fuel consumed, as the water-pres- England. It is known as Bishop's process, sure rises from 15 lbs. to 40 lbs. Beyond this and is described in an address delivered by Mr. point there does not appear to be much ad- Jolin Mayer in the Chemical Section of the vantage gained by still further increasing the Glasgow Philosophical Society. In this syspressure. The gas produced is essentially a non- tem the kiln consists of a series of four calcinluminous gas. When taken direct from the pro- ing chambers arranged vertically over each ducer, it burns with a reddish-blue flame. Af- other, and, together with the furnace underter having, however, been stored in a gas-hold- neath them, occupying the space of one of the er for a few hours in contact with water, the ovens of the retort-bench. They are about 9 flame loses this red tinge, and the gas burns with feet long and 24 feet wide. Ill the chambers a blue lightless flame very much resembling are constructed of fire-clay tiles and blocks of ordinary gas burned in the Bunsen burner. In similar form. The gases from the furnace neither case is there any smoke, soot, or de- pass backward to its farther end, and rising posit of any kind by the burning gas, the sole enter, by ineans of two ports at the corners, products of combustion being water and car the lowermost calcining chamber, thence over bonic anhydride. When the gas is made in the top of and in close contact with the spent considerable quantity, its cost in London is lime, to the fore end of the same; and thence about a quarter of that of ordinary illuminat- up through two ports as before, traversing the ing gas.

second chamber in the same way; then the The Equivalent of Gallium.-Lecoq de Bois- third chamier; and, lastly, the topmost or bandran has determined the equivalent of gal- drying chamber, from which they enter the lium by the calculation of gallo-ammoniacal main Hue, the opening into which is regulated alum, and by igniting the gallium nitrate pro- by a suitable damper. The spent lime is first duced froin a known weight of the metal. The charged into the drying chamber by means of slight losses sustained in these two operations a shovel, and it remains in that chunber duraffect the value of the equivalent in an opposite ing the regeneration of the contents of the

The former process gave as the re chambers underneath; and after the latter sult 70·032 (hydrogen being 1), and the latter have been discharged into an iron wagon or 69.698. The mean value, 69.865, may be taken barrow, the contents of the upper chamber are as the first approximation. Considerations discharged into the lower chambers through a founded on a classification of the elements in port near the front of each, the opening of accordance with their properties and the value which is covered with a suitable tile, as the of their atomic weights point to a maximum chambers are successively filled, commencing number, 69.97, and a minimum, 09•66 (mean, at the lowermost; and the gases from the fur69:82). The author enters into some details on nace, while passing over and in close contact the comparison of the spectra of the metals with the spent lime, (lisengage the carbonio Al, Ga, In, on the one hand, and K, Rb, Cs, on acid and other impurities. Air is admitted the other, and deduces hence for the equivalent through ventilating flue-boxes, placed on either of gallium the value 69.86.

side of the furnace near to the ground, whence Nero Compound of Palladium.In a com it is conveyed to and directed against the fuel munication to the Paris Academy of Sciences in the furnace near to the center of the furnaceH. Ste.-Claire Deville and II. Debray recite bars, where it issues from a number of holes that, on heating a solution of palladium chloride about 14 inch in diameter, pierced through fire(Pučl) with strong nitric acid in presence of clay blocks, which form part of the sides of sal-ammoniac, the palladinm is converted into the furnace. These air-loles pass through the an ammonia chloride (PdCl. + NH4Cl), which blocks with a dip of about 14 inch toward the precipitates in small regular octahedrons of a furnace-bars. In practice it is found that one fine red color, sparingly soluble in water, and, man can attend to two sets of chambers, such as like the corresponding compounds of iridium those just described, and regenerate upward of and platinum, almost insoluble in a concentrat- 50 cwt. of spent lime per shift of twelve hours, ed solution of sal-ainmoniac. The authors ex with a consumption of about 8 cwt. of fuel, pected th in heating with aqua regia certain which is usually the coke of ordinary cannel mother-liquors containing ammoniacal palla- coal. diuin chloride (dipalladamine chloride, Paol, LIydrogen Peroxide.—The amount of hydro

inanner.

gen peroxide in the air and in atmospheric de- tion of hydrogen peroxide containing 3 or 4 per cent. posits is the subject of a recent exhaustive re

was mixed with a 10 per cent, sodium-hydrate soluport by Schöne, of Moscow. llis investiga- C. took place with a very slight ovolution of gas.

tion, in equivalent proportions. A rise of 4 or 5° tions extended from July 1, 1874, to June 30, On concentrating the solution in a vacuum, effores1875, and were conducted with wonderful cent crystals separated on the edges at first, and then patience and care. Ile examined 215 speci- large tabular crystals formed in the solution. If, inmens of rain and hail, and snow and sleet stead of evaporating the solution, once and a half or

twice its volume of absolute alcohol be added, and were tested on 172 occasions. Seven samples it be allowed to stand in a cool place for twenty-four of rain and 86 of snow appeared to contain no hours, spear-shaped crystals, often several centiperoxide.

metres long, appear in the solution. On analysis The deposits brought by the equatorial currents

they give numbers agreeing with the formula Ná,0, always contained more peroxide than those falling (11.0: They are identical with those obtained at times when the polar currents opposed them; uni luter by Fairly in the same manner, and with those

obtained by Vernon llarcourt by solution of sodium when the polar stream of air predominates, the rela

dioxide in water. When rapidly heated in a glass tively smallest yield of peroxide is obtained. The amount attained a minimum in December and Janu- tube, the crystals melt, froth, evolve oxygen and ary, very slowly increased until April, was very much leave sodium hydrate. In closed vessels, the same liigher during Ilay and June on to July, when it cul- decomposition takes place more slowly, requiring minated. During the next three monthis it tell rapid

three months for completion. Absolute alcohol prely, and in November again very slowly approached On examining'the citlorescence above mentioned, it

serves it pretty well, it carbon dioxide be excluded. the minimum. The hail of summer contained a comparatively large amount otthe peroxide, although described ind of another substance having the for

was found to be a mixture of the substance already it is less abundant in hail than in rain; and the winter rain yields more of this compound than snow

mula Va.I1,0);, or Nay()( 11.02)2, a conipound of so

dium peroxide with hydrogen peroxide. To prefalling at the same period. The total amount of

pare it, a mixture of one molecule of sodium hydrate hydrogen peroxide which reached the eartli's sur

and about three and a half molecules of liydrogen face during the year is computed by the author to have amounted to 109.4 milligrames to the square

peroxide solution are mixed and evaporated in

vacuo. The crystals are colorless and very minute, metre-that is to say, in 599-9 litres of water, or 1•049 kilog to the hectare. The peroxide present solve in this and in dilute acids without evolution

are at first trausparent, very soluble in water, disin the air in a state of vapor was collected and determined by producing artificial dew with the

of gas, and «tiloresce in dry air. In vacuo over sulaid of freezing mixtures; and it was found that the phuric acid they lose four molecules of water, leavrisc and fall in the amount so obtained correspond- ing Na-1!,9. A similar peroxide hydrate was obed and went hand in hand with the numbers ob

tained with potassium, though mixing the solutions tained by testing the atmospheric deposits. The

and evaporating gave only a yellow amorphous mixdiurnal variation was studlied, and it was ascertained

ture of potassium tetroxide and potassium hydrate, that the maximum amount was present at about 4

KO+KOJI+11,0)),.. But if excess of hydrogen c clock in the afternoon, after which it diminished, der det be used, and the cvaporation be conducted the minimum being attained between midnight and

100 (., a white opaque mass

results, which is very hygroscopic and has the for4 A. M. The air of a large hall, which had been m

mula K 11,0), or K209(11,0,12. These facts the auoccupied for four weeks and the windows of which

thor uses to explain the " catalytic" action, as folwere closed but were not air-tight, was observed to

lows: The decomposition of hydrogen peroxide in contain an average of' 0:17 C. c. peroxide in 1.000 cubic

alkaline solutions is due, first, to the tendency of metres. Iu dew artificially deposited in a badly ven

the alkalies to form compounds of the composition tilated room there was no peroxide; its presence, R,I1,(or R.O. (ILO,',; second, to the tendency however

, became manifest as soon as the windows of the alkali metal within this compound to oxidize were thrown open. Dew and hoar frost deposited itself to a higher oxide, the tetroxide; and, third, to during the last hours of the night appeared to be pure the reduction of the tetroxide to dioxide by the water water; in dew collected during the evening hours

present. peroxide was met with, the amount being 0:05 gramme to the litre. The peroxide is present in for, Ver Discorery in Thermo-Chemistry.-A and is apparently more abundant in spring than in discovery of importance in thermo-chemistry autumn." The amount of perosiile present in any

has been communicated to the Paris Academy atmospheric deposit varies with the altitude at which that deposit has been formed; the greater the alti

of Sciences, by M. Maumené. Concentrated tude at which tho condensation takes place, the sulphuric acid, he writes, which has been left greater is the quantity of peroxide which it will con for some months standing, undergoes a singutain. This is doubtiess ilue to the decomposition lar change of condition. On mixing a liquid organic vapors rising from the earth's surface. In such as olive oil withi, say, one tenth of its the air itself there is but little peroxide, the maxi-weight of fresh concentrated acid, a certain mum quantity observed being 14c.c. in 1,000 cubic constant rise of temperature is observed; but metres of air. The author points out tho scientific if acid three months old is used, the rise of advantages which would attend systematic observa- temperature so obtained has a value of about tion in this field at meteorological stations.

go Cent. less. The saune results occur even if The same author has investigated the rela- the acid has been hermetically sealed in glass tions of hydrogen peroxide to the alkalies, with tubes. With water and other liquids analogons particular reference to the decomposing action results are found. It is evident that somo of of the latter on the former. Of this research the most important data of the thermal effects we append an excellent summary, published in of chemical action may require revising in the the “ American Journal of Science":

light of this discovery. IIis first efforts were directed to the production

Neu Jethod or separating Arsenic and Anof peroxide hydrates of the alkalies analogous to timony.-A new modo of separating arsenic whose of the alkaline earths. For this purpose a solu- from other metals is offered by Messrs. De

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