On the Economy of Machinery and Manufactures - Charles Babbage (interesting books to read in english .TXT) 📗

to the other end of the table. The object of this process

is to straighten the wire, which had acquired a considerable

curvature in the small coils in which it had been wound. The

length thus straightened is cut off, and the remainder of the

coil is drawn into similar lengths. About seven nails or pins are

employed in straightening the wire, and their adjustment is a

matter of some nicety. It seems, that by passing the wire between

the first three nails or pins, a bend is produced in an opposite

direction to that which the wire had in the coil; this bend, by

passing the next two nails, is reduced to another less curved in

the first direction, and so on till the curve of the wire may at

last be confounded with a straight line.

 

230. 3. Pointing. (a) A man next takes about three hundred of

these straightened pieces in a parcel, and putting them into a

gauge, cuts off from one end, by means of a pair of shears, moved

by his foot, a portion equal in length to rather more than six

pins. He continues this operation until the entire parcel is

reduced into similar pieces. (b) The next step is to sharpen the

ends: for this purpose the operator sits before a steel mill,

which is kept rapidly revolving: it consists of a cylinder about

six inches in diameter, and two and a half inches broad, faced

with steel, which is cut in the manner of a file. Another

cylinder is fixed on the same axis at a few inches distant; the

file on the edge of which is of a finer kind, and is used for

finishing off the points. The workman now takes up a parcel of

the wires between the finger and thumb of each hand, and presses

the ends obliquely on the mill, taking care with his fingers and

thumbs to make each wire slowly revolve upon its axis. Having

thus pointed all the pieces at one end, he reverses them, and

performs the same operation on the other. This process requires

considerable skill, but it is not unhealthy; whilst the similar

process in needlemaking is remarkably destructive of health. (c)

The pieces now pointed at both ends, are next placed in gauges,

and the pointed ends are cut off, by means of shears, to the

proper length of which the pins are to be made. The remaining

portions of the wire are now equal to about four pins in length,

and are again pointed at each end, and their lengths again cut

off. This process is repeated a third time, and the small portion

of wire left in the middle is thrown amongst the waste, to be

melted along with the dust arising from the sharpening. It is

usual for a man, his wife, and a child, to join in performing

these processes; and they are paid at the rate of five farthings

per pound. They can point from thirty-four to thirty-six and a

half pounds per day, and gain from 6s. 6d. to 7s., which may be

apportioned thus; 5s. 6d. the man. 1s. the woman, 6d. to the boy

or girl.

 

231. 4. Twisting and cutting the heads. The next process is

making the heads. For this purpose (a) a boy takes a piece of

wire, of the same diameter as the pin to be headed, which he

fixes on an axis that can be made to revolve rapidly by means of

a wheel and strap connected with it. This wire is called the

mould. He then takes a smaller wire, which having passed through

an eye in a small tool held in his left hand, he fixes close to

the bottom of the mould. The mould is now made to revolve rapidly

by means of the right hand, and the smaller wire coils round it

until it has covered the whole length of the mould. The boy now

cuts the end of the spiral connected with the foot of the mould,

and draws it off. (b) When a sufficient quantity of heading is

thus made, a man takes from thirteen to twenty of these spirals

in his left hand, between his thumb and three outer fingers:

these he places in such a manner that two turns of the spiral

shall be beyond the upper edge of a pair of shears, and with the

forefinger of the same hand he feels that only two turns do so

project. With his right hand he closes the shears; and the two

turns of the spiral being cut off, drop into a basin; the

position of the forefinger preventing the heads from flying about

when cut off. The workmen who cut the heads are usually paid at

the rate of 2 1/2d. to 3d. per pound for large heads, but a

higher price is given for the smaller heading. Out of this they

pay the boy who spins the spiral; he receives from 4d. to 6d. a

day. A good workman can cut from six to about thirty pounds of

heading per day, according to its size.

 

232. 5. Heading. The process of fixing the head on the body

of the pin is usually executed by women and children. Each

operator sits before a small steel stake, having a cavity, into

which one half of the intended head will fit; immediately above

is a steel die, having a corresponding cavity for the other half

of the head: this latter die can be raised by a pedal moved by

the foot. The weight of the hammer is from seven to ten pounds,

and it falls through a very small space, perhaps from one to two

inches. The cavities in the centre of these dies are connected

with the edge of a small groove, to admit of the body of the pin,

which is thus prevented from being flattened by the blow of the

die. (a) The operator with his left hand dips the pointed end of

the body of a pin into a tray of heads; having passed the point

through one of them, he carries it along to the other end with

the forefinger. He now takes the pin in the right hand, and

places the head in the cavity of the stake, and, lifting the die

with his foot, allows it to fall on the head. This blow tightens

the head on the shank, which is then turned round, and the head

receives three or four blows on different parts of its

circumference. The women and children who fix the heads are paid

at the rate of 1s. 6d. for every twenty thousand. A skilful

operator can with great exertion do twenty thousand per day, but

from ten to fifteen thousand is the usual quantity: children head

a much smaller number: varying, of course, with the degree of

their skill. About one per cent of the pins are spoiled in the

process; these are picked out afterwards by women, and are

reserved, along with the waste from other processes, for the

melting-pot. The die in which the heads are struck is varied in

form according to the fashion of the time; but the repeated blows

to which it is subject render it necessary that it should be

repaired after it has been used for about thirty pounds of pins.

 

233. 6. Tinning. The pins are now fit to be tinned, a process

which is usually executed by a man, assisted by his wife, or by a

lad. The quantity of pins operated upon at this stage is usually

fifty-six pounds. (a) They are first placed in a pickle, in order

to remove any grease or dirt from their surface, and also to

render them rough, which facilitates the adherence of the tin

with which they are to be covered. (b) They are then placed in a

boiler full of a solution of tartar in water, in which they are

mixed with a quantity of tin in small grains. In this they are

generally kept boiling for about two hours and a half, and are

then removed into a tub of water into which some bran has been

thrown, for the purpose of washing off the acid liquor. (c) They

are then taken out, and, being placed in wooden trays, are well

shaken in dry bran: this removes any water adhering to them; and

by giving the wooden tray a peculiar kind of motion, the pins are

thrown up, and the bran gradually flies off, and leaves them

behind in the tray. The man who pickles and tins the pins usually

gets one penny per pound for the work, and employs himself,

during the boiling of one batch of pins, in drying those

previously tinned. He can earn about 9s. per day; but out of this

he pays about 3s. for his assistant.

 

234. 7. Papering. The pins come from the tinner in wooden

bowls, with the points projecting in all directions: the

arranging of them side by side in paper is generally performed by

women. (a) A woman takes up some, and places them on a comb, and

shaking them, some of the pins fall back into the bowl, and the

rest, being caught by their heads, are detained between the teeth

of the comb. (b) Having thus arranged them in a parallel

direction, she fixes the requisite number between two pieces of

iron, having twentyfive small grooves, at equal distances; (c)

and having previously doubled the paper, she presses it against

the points of the pins until they have passed through the two

folds which are to retain them. The pins are then relieved from

the grasp of the tool, and the process is repeated. A woman gains

about 1s. 6d. per day by papering; but children are sometimes

employed, who earn from 6d. per day, and upwards.

 

235. Having thus generally described the various processes of

pinmaking, and having stated the usual cost of each, it will be

convenient to present a tabular view of the time occupied by each

process, and its cost, as well as the sums which can be earned by

the persons who confine themselves solely to each process. As the

rate of wages is itself fluctuating, and as the prices paid and

quantities executed have been given only between certain limits,

it is not to be expected that this table can represent the cost

of each part of the work with the minutest accuracy, nor even

that it shall accord perfectly with the prices above given: but

it has been drawn up with some care, and will be quite sufficient

to serve as the basis of those reasonings which it is meant to

illustrate. A table nearly similar will be subjoined, which has

been deduced from a statement of M. Perronet, respecting the art

of pinmaking in France, above seventy years ago.

 

English manufacture

 

236. Pins, Elevens, 5546 weigh one pound; one dozen = 6932

pins weigh twenty ounces, and require six ounces of paper.

 

Name of the process

Workman

Time for making 1 lb of pins Hours

Cost of making 1 lb of pins Pence

Workmen earns per day s. d.

Price of making each part of a single pin in millionths of a

penny

 

1. Drawing wire (224) Man .3636 1.2500 3 3 225

2. Straightening wire ( 225) Woman .3000 .2840 1 0 51

Girl .3000 .1420 0 6 26

3. Pointing (226) Man .3000 1.7750 5 3 319

4. Twisting and cutting heads Boy .0400 .0147 0 4 1/2 3

(227) Man .0400 .2103 5 4 1/2 38

5. Heading (228) Woman 4.0000 5.0000 1 3 901

6 Tinning or whitening Man .1071 .6666 6 0 121

(229) Woman .1071 .3333 3 0 60

7. Papering (230) Woman 2.1314 3.1973 1 6 576

7.6892 12.8732 - - 2320

 

Number of persons employed: Men. 4; Women. 4;