Marchi, Monumenti delle arti cristiane primitive (Rome, 1844); Raoul Rochette, Tableau des catacombes de Rome (2nd ed., Paris, 1853) Perret, Les Catacombes de Rome (Paris, 1855) - a sumptuous folio work, but not always accurate; Roller, Les Catacombes de Rome (Paris, 1881); V.
- Roller of Washing Machine.
This device consists of a roller of radius r, pressed into contact with a disk.
The wonderful development of Minnesota as a flour-producing state began with the introduction of improved roller processes after 1870.
Among its manufactures are agricultural machinery (especially seeding machines) and tools, automobiles, pianos, lawn-mowers, roller-skates, foundry and machine-shop products, furniture, burial caskets, and flour.
The glass is taken from the furnace in large iron ladles, which are carried upon slings running on overhead rails; from the ladle the glass is thrown upon the cast-iron bed of a rolling-table, and is rolled into sheet by an iron roller, the process being similar to that employed in making plate-glass, but on a smaller scale.
The pattern is impressed Upon the soft sheet by a printing roller which is brought down upon the glass as it leaves the main rolls.
When the crop is luxuriant it is necessary to put a roller over it first, to facilitate proper burial by the plough.
The two are carried on a common frame, so arranged that a change in form of the spring causes a relative displacement of the disk and roller, the point of contact moving radially from or towards the centre of the disk.
This is a drawing machine fitted with fallers through which the sliver is drawn, but the end from the front roller is wound on to a bobbin.
Another type of machine termed the three pair roller jute opener is illustrated in fig.
The proximity of the weighted roller or rollers to the fixed ones depends upon the large cylinder.
After passing the last pair of workers and strippers the fibre is carried forward towards the doffing roller, the pins of which are back-set, and the fibre is removed from the cylinder by the doffer, from which it passes between the drawing and pressing rollers into the conductor, and finally between the delivery and pressing rollers into the sliver can.
The ratio of the surface speeds of the drawing roller and the feed roller is termed the draft: surface speed of drawing roller _ draft.
The first roller press was made by the A.
Then, if a current is sent from the spring to the roller through the paper, a brown mark will be mace by the spring due to the liberation of iodine.
The motor is usually supported on a platform at the back of the instrument, its drivingwheel being connected to the shaft of the paper roller by means of a spirally wound steel band.
In the first state the prints have been taken off with the roller, or even by handpressing, and they are weak in tint; in the second state the printing press has been used, and the ink is stronger.
He mentions the different kinds of wheat, barley and oats; and after describing the method of harrowing " all maner of cornnes," we find the roller employed.
Improvements in the plough, harrow and roller were introduced, adapting those implements to different soils and purposes.
In the Macarthy roller gin, the lint, drawn by a roller covered with leather (preferably walrus hide), is drawn between a metal plate called the " doctor " (fixed tangentially to the roller and very close to it) and a blade called the " beater " or knife, which rapidly moves up and down immediately behind, and parallel to, the fixed plate.
A hand Macarthy roller gin worked by two men will clean about 4 to 6 lb of lint per hour.
Opposed to the various types of roller gins is the " saw gin," invented by Eli Whitney, an American, in 1792.
The crop is picked, ginned and baled in the usual way, the Macarthy style action roller gins being almost exclusively employed.
The coagulum is next flattened out by a wooden or iron roller to get rid of the cavities containing watery liquid, and the sheets are then hung up for fourteen days to dry, when they weigh about 2 lb, the sheets being usually z to a in.
A mass of glass in a viscous state can be rolled with an iron roller like dough; can be rendered hollow by the pressure of the human breath or by compressed air; can be forced by air pressure, or by a mechanically driven plunger, to take the shape and impression of a mould; and can be almost indefinitely extended as solid rod or as hollow tube.
The viscous mass having been thrown on the casting-table, a large and heavy roller passes over it and spreads it out into a sheet.
The width of the sheet or plate is regulated by moving guides which are placed in front of the roller and are pushed along by it, while its thickness is regulated by raising or lowering the roller relatively to the surface of the table.
If do is the angular displacement of the roller corresponding to displacements, dO of the disk, and ds of the point of application of P, a, and C constants, then d4) = x _ ¢Pds = C.Pds, and therefore 4) = C f 82 Pds; that is, the angular displacement of the roller measures the work done during the displacement from s 1 to s 2 .
The shaft carrying the roller is connected to a counter so that 4 may be observed.
The block A carries the disk D, B carries the roller R and counting gear.
The distance between the rollers can be easily regulated so that the seed leaving the bottom roller has the desired fineness.
In all roller machines used at that time the plain sheets of wax were first made by the " dipping " process, i.e.
The importance of the flour manufacturing industry was originally due to the excellent water-power available, and dates from the introduction of improved roller-mill methods in the early 'seventies, although there were successful mills in operation twenty years earlier.
Two pieces of wood are placed at two ends, which are tied to the ohari and okher or roller; they are made fast to the khoti.
The fibre, which should be arranged on the sheet as evenly as possible, is carried up by the feed cloth and passes between the feed roller and the shell on to the small knobs.
Two of these rollers are supported in the same horizontal plane of the framework, while the third or top roller is kept in close contact by means of weights and springs acting on each end of the arbor.
Surface speed of feed roller In this machine the draft is usually about thirteen.
During the interval between taking off the printed sheet and laying on the next one his partner inks the type surface with a roller which carries just sufficient ink properly distributed to preserve uniformity of " colour."
The ink passes to a small solid metal roller, and is then conveyed by a vibrating roller made of composition to a larger and hollow metal cylinder or drum which distributes the ink for the first time.
A second vibrating composition roller conveys the ink from this drum to the distributing table or ink slab, on which other rollers, called distributors, still further thin out the ink.
In the first case a bar descends upon the paper after it is laid to point marks, and this bar, having a rotary motion, runs the sheet between a roller and a small drum into the machine.