Journal of the Franklin Institute

MEAT BREAD.

M. Scheurer-Kestner has discovered the remarkable fact that the ermentation of bread causes the complete digestion of meat. He found hat a beef steak cut into four pieces, and mixed with flour and yeast, isappeared entirely during the process of fermentation, its nutritive rinciples becoming incorporated with the bread. The meat would lso appear capable of preservation for an indefinite period in its new tate, for loaves of meat bread, made in 1873 have been submitted to he French Academy of Science, when not a trace of worms or mouldiess was observable. At the beginning of his experiments, M. ScheurerKestner used raw meat, three parts of which, finely minced, he mixed vith five parts of flour and the same quantity of yeast. Sufficient water was added to make the dough, which in due time began to ferment. After two or three hours, the meat had disappeared, and the bread vas baked in the ordinary manner. Thus prepared, the meat bread ad a disagreeable, sour taste, which was avoided by cooking the meat or an hour with sufficient water to afterwards moisten the flour. The neat must be carefully deprived of fat, and only have sufficient salt to ring out the flavor, as salt, by absorbing moisture from the air, would end to spoil the bread. A part of the beef may be replaced with dvantage by salt lard, which is found to improve the flavor. The roportion of meat to flour should not exceed one half, so as to insure omplete digestion. Bread made with a suitable proportion of veal is aid to furnish excellent soup for the sick and wounded.-Sanitary Record.

Crystalline Form of Magnesium.-Des Cloizeaux has exaained some beautiful crystals of magnesium, which were presented to he French Academy by M. Dumas. The crystals were obtained by ublimation and are of a white color, with the brilliancy of silver. Their faces are often curved and the edges blunt; the usual form is hat of a regular hexagonal prism, terminated by a base which is a ttle less brilliant than the lateral faces. The edges of the base are ften replaced by an annular truncation, the combination of which with the faces of the prism recalls that of tellurium crystals. The lminating angle is more acute than in the other rhombohedral metals, senic, tellurium, antimony and bismuth. The crystals are very malable and sectile, but without visible cleavage.-Compt. Rend. C.

Earthen Filtering Plates.-G. W. Reye & Sons, of Hamburg, make filtering plates from a mixture of one part of gypsum with three parts of imperial earth in water. They can be purified after using by washing or burning. When impregnated with carbolic acid they also become useful as disinfectants.-Dingler's Journal. C.

Electric Sun. Lontin has been exhibiting in the building of the Industrial Exhibition in the Champs Elysées, Paris, a circular electric light, formed by four voltaic arches. He uses four carbons placed radially, the two which are in the same diameter being connected with the same pole, so that an arch extends from each of the carbons to each of its neighbors. These four arches unite to form a complete circle and produce a light of extraordinary brilliancy.—Dingl. Jour. C.

Dissociation of Metalloids.-Pictet proposes a plan which he thinks might effect the dissociation of metalloids, but which is too costly for him to undertake at his own expense. It consists of a parabolic mirror, with a section normal to the sun's rays which should have at least 35 metres (41.86 sq. yards) of surface. He estimates that this would give a heat equivalent to 1000 calorics (2200 thermal units) per minute, and that such a heat would probably be sufficient to decompose any of the metalloids which are really compound bodies.- Les Mondes.

An Intensified Electro-Magnet.-Dr. Stone recently exhibited before the Physical Society a very interesting electro-magnet of novel constructiou, and based on a principle which will probably be applied with advantage in the construction of electro-magnets for dynamoelectric machines and telegraphic apparatus. It is known that electromagnets enclosed in jackets of soft iron are far more powerful than when the copper coil of wire is unenclosed. In fact, the iron jacket, like the second armature or diaphragm in M. Ader's form of Bell telephone recently described by us, has the effect of exalting the magnetic power of the poles. Dr. Stone does not employ a soft iron jacket, but instead of using copper wire to wind the bobbins he uses best charcoal annealed iron wire about in. in diameter, Four wires are wound on in parallel circuits, and the current is split up among them in "multiple arc." They are insulated from each other by paraffine wax. By this felicitous arrangement the lifting power of Dr. Stone's large magnet is, with a battery of four or five Bunsen cells, increased fourfold.-Engineering.

COMMUNICATIONS.

U. S. NAVAL OBSERVATORY,
Washington, D. C., June 15, 1880.

Committee on Publication of the Franklin Institute Journal:

GENTLEMEN:-Some months ago I had occasion to investigate the strength of a particular class of gearing, and now it seems desirable to extend the investigation to all kinds of gearing. The numerical values of the coefficients in my formula can only be determined from wheels in actual use, which are known to be working up to their full capacity. The data required are:

1. The material composing the wheel.

2. Its diameter at the pitch line.

3. The width of its face.

The number of its teeth.

.. Its pitch.

. The number of revolutions it makes per minute.

. The number of horse-power transmitted by it; or, the pressure ounds at its pitch line.

A statement of the kind of machinery it drives.

hese data will be of no value unless it is known that the wheel is king up to its full capacity, and in every case the reasons for supng that it is doing so should be stated.

he method of determining the pressure at the pitch line should be stated. If the wheel transmits the full power of an engine, ctual, not its nominal, horse-power should be given. In such the power should be determined from indicator diagrams, if ible. When that cannot be done the following particulars should pecified concerning the engine:

Condensing or non-condensing.

Diameter of piston.

Length of stroke.

Number of revolutions per minute.

Pressure of steam.

Point at which the steam is cut off.

ay I appeal to your readers to furnish me such information? If

enough is forthcoming to yield a satisfactory result, I will be very happy, with your permission, to publish my investigation in your Journal; and full credit will be given to all who have furnished data. Yours, very respectfully,

WM. HARKNESS.

WOOD PRESERVATION.

To Engineers, Architects, Preservers of Wood, Chemists, and Others:

The undersigned, a Committee of the American Society of Civil Engineers appointed to report upon the Preservation of Timber, earnestly solicit information concerning past experience in the impregnation and preservation of that material.

Particulars of failures in this country, and if possible the reasons therefor, are specially desired. Also, information on the following points, in each of the processes, which may have been used:

1. Kind of timber operated on-green or dry-age, dimensions, etc. 2. Preserving ingredients injected.

3. Quantity injected per cubic foot or tie.

4. Mode of application, process, time employed, degree of heat, pressure, vacuum, etc.

5. Subsequent use and exposure of timber (bridges, buildings, or track).

6. Result of preparation and comparison with life of unprepared timber.

This special and any general information on the subject is respectfully solicited.

Replies can be mailed to the chairman of the committee.

B. M. HARROD, Chairman,

122 Common Street, New Orleans, La.

G. Bouscaren, 82 West Third St., Cincinnati, O.

E. R. Andrews, 10 Warren St., New York City, N. Y.

E. W. Bowditch, 60 Devonshire St., Boston, Mass.