of the same materials and proportions.
Sewers made on this plan may have the centering removed in eight hours, and in four or five days they may be used.
Arches with a pitch of 1 in 10 have proportions, sand 5, lime 1, hydraulic cement,. 5.
In Paris, arches, floors, foundations, barracks, and churches are made of this material.
A dwelling of five stories, in Miromesnil Street, Paris, is constructed of a single mass of beton; a staircase of the same material runs in helicoidal form from theand allowed to remain for 12 hours, 15 or 16 fresh layers of the composition being added in succession until the bougies are brought to the required size.
They are next polished with pumice-stone, and afterwards smoothed with tripoli and oil. In Paris, which is the chief seat of the manufacture of these articles, one seventh of its weight of caoutchouc is dissolved in the oil, to render the compound more solid.
For this purpose the caoutchouc is cut into slender filaments and added to the ho
crew is driven by bevel-gear fixed on the shaft of the driving-wheels and on the axis of the screw.
Parkins's railroad consists of a carriage traversing on rollers and drawn by a rope.
It is said to have had a trial in the neighborhood of Paris, France.
It is an absurd affair.
The carriages have a bearing upon three or four sets of wheels at a time, and the rails are on the carriage, so to speak, a plated bar resting on the rails.
It is an inversion of the ordinary mode, wheels in pedeod when things became lively in this line.
Since this period nearly 3,000 patents have been granted in the United States for harvesters and attachments therefor.
In the summer of 1855, at a competitive trial of reapers about 40 miles from Paris, France, three machines were exhibited, from America, England, and Algiers.
The following was the result in a field of oats:—
The American machine cut an acre in22 minutes.
The English machine cut an acre in66 minutes.
The Algerian machine cut
ed, the liquid matter drawn off into the Thames, and the solid sold for agricultural purposes.
Sewers (London and Paris patterns).
In Fig. 4844, a illustrates the shape and dimensions of a sewer employed in some of the London districts.
In Paris, the form b is generally employed, c is used in the Westminster district, London.
This form is not calculated to give the greatest strength, and in some instances the sides have been crushed in by the pressure.
An oval form d e is adopted byal brush.
Ancient Rome had its cloacae, and so had its beautiful colony Augsburg; but the cleaning of streets, except in exceptional cases, as in the splendid capital of the Spanish Caliphs, Cordova, was in a beastly state of inefficiency.
In Paris, in 1285, under Philip the Bold, an order was issued that each citizen should keep the street clean in front of his own house.
In 1348 and 1388 stringent penalties were enacted against the remiss, and a dirt and garbage cart (un tombereau) was
nd wheel forms the ornament near the middle.
A third wheel provided with points makes the indentations on the side and end The inside is then polished in a similar way to that employed for the outside.
The thimbles are finally boiled in soapsuds to remove the oil, and then brushed.
Iron thimbles for sewing are raised by stamping with five or six blows, between as many pairs of conical dies, which are successively more and more salient.
The metal is annealed between each operation.
In Paris they are made from strips of thin sheet-iron, which is punched into disks about two inches in diameter; these are heated red-hot, struck up to the required depth, then placed in the lathe, where the interior is polished, the outside turned off, the pits indented with a kind of milling tool, and a groove formed on the outside to receive the gilding.
After being annealed and brightened, the inside is also gilt with a strip of goldleaf applied by the pressure of a mandrel.
A fillet of gold-l