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

competition amongst

the masters, the apprentice will be able to make better terms,

and diminish the period of his servitude. Again, the facility of

acquiring skill in a single process, and the early period of life

at which it can be made a source of profit, will induce a greater

number of parents to bring up their children to it; and from this

circumstance also, the number of workmen being increased, the

wages will soon fall.

 

219. 2. Of waste of materials in learning. A certain quantity

of material will, in all cases, be consumed unprofitably, or

spoiled by every person who learns an art; and as he applies

himself to each new process, he will waste some of the raw

material, or of the partly manufactured commodity. But if each

man commit this waste in acquiring successively every process,

the quantity of waste will be much greater than if each person

confine his attention to one process; in this view of the

subject, therefore, the division of labour will diminish the

price of production.

 

220. 3. Another advantage resulting from the division of

labour is, the saving of that portion of time which is always

lost in changing from one occupation to another. When the human

hand, or the human head, has been for some time occupied in any

kind of work, it cannot instantly change its employment with full

effect. The muscles of the limbs employed have acquired a

flexibility during their exertion, and those not in action a

stiffness during rest, which renders every change slow and

unequal in the commencement. Long habit also produces in the

muscles exercised a capacity for enduring fatigue to a much

greater degree than they could support under other circumstances.

A similar result seems to take place in any change of mental

exertion; the attention bestowed on the new subject not being so

perfect at first as it becomes after some exercise.

 

221. 4. Change of tools. The employment of different tools in

the successive processes is another cause of the loss of time in

changing from one operation to another. If these tools are

simple, and the change is not frequent, the loss of time is not

considerable; but in many processes of the arts the tools are of

great delicacy, requiring accurate adjustment every time they are

used; and in many cases the time employed in adjusting bears a

large proportion to that employed in using the tool. The

sliding-rest, the dividing and the drilling-engine, are of this

kind; and hence, in manufactories of sufficient extent, it is

found to be good economy to keep one machine constantly employed

in one kind of work: one lathe, for example, having a screw

motion to its sliding-rest along the whole length of its bed, is

kept constantly making cylinders; another, having a motion for

equalizing the velocity of the work at the point at which it

passes the tool, is kept for facing surfaces; whilst a third is

constantly employed in cutting wheels.

 

222. 5. Skill acquired by frequent repetition of the same

processes. The constant repetition of the same process

necessarily produces in the workman a degree of excellence and

rapidity in his particular department, which is never possessed

by a person who is obliged to execute many different processes.

This rapidity is still further increased from the circumstance

that most of the operations in factories, where the division of

labour is carried to a considerable extent, are paid for as

piece-work. It is difficult to estimate in numbers the effect of

this cause upon production. In nail-making, Adam Smith has

stated, that it is almost three to one; for, he observes, that a

smith accustomed to make nails, but whose whole business has not

been that of a nailer, can make only from eight hundred to a

thousand per day; whilst a lad who had never exercised any other

trade, can make upwards of two thousand three hundred a day.

 

223. In different trades, the economy of production arising

from the last-mentioned cause will necessarily be different. The

case of nail-making is, perhaps, rather an extreme one. It must,

however, be observed, that, in one sense, this is not a permanent

source of advantage; for, though it acts at the commencement of

an establishment, yet every month adds to the skill of the

workmen; and at the end of three or four years they will not be

very far behind those who have never practised any other branch

of their art. Upon an occasion when a large issue of banknotes

was required, a clerk at the Bank of England signed his name,

consisting of seven letters, including the initial of his

Christian name, five thousand three hundred times during eleven

working hours, besides arranging the notes he had signed in

parcels of fifty each.

 

224. 6. The division of labour suggests the contrivance of

tools and machinery to execute its processes. When each

processes, by which any article is produced, is the sole

occupation of one individual, his whole attention being devoted

to a very limited and simple operation, improvements in the form

of his tools, or in the mode of using them, are much more likely

to occur to his mind, than if it were distracted by a greater

variety of circumstances. Such an improvement in the tool is

generally the first step towards a machine. If a piece of metal

is to be cut in a lathe, for example, there is one particular

angle at which the cutting-tool must be held to insure the

cleanest cut; and it is quite natural that the idea of fixing the

tool at that angle should present itself to an intelligent

workman. The necessity of moving the tool slowly, and in a

direction parallel to itself, would suggest the use of a screw,

and thus arises the sliding-rest. It was probably the idea of

mounting a chisel in a frame, to prevent its cutting too deeply,

which gave rise to the common carpenter’s plane. In cases where a

blow from a hammer is employed, experience teaches the proper

force required. The transition from the hammer held in the hand

to one mounted upon an axis, and lifted regularly to a certain

height by some mechanical contrivance, requires perhaps a greater

degree of invention than those just instanced; yet it is not

difficult to perceive, that, if the hammer always falls from the

same height, its effect must be always the same.

 

225. When each process has been reduced to the use of some

simple tool, the union of all these tools, actuated by one moving

power, constitutes a machine. In contriving tools and simplifying

processes, the operative workmen are, perhaps, most successful;

but it requires far other habits to combine into one machine

these scattered arts. A previous education as a workman in the

peculiar trade, is undoubtedly a valuable preliminary; but in

order to make such combinations with any reasonable expectation

of success, an extensive knowledge of machinery, and the power of

making mechanical drawings, are essentially requisite. These

accomplishments are now much more common than they were

formerly, and their absence was, perhaps, one of the causes of

the multitude of failures in the early history of many of our

manufactures.

 

226. Such are the principles usually assigned as the causes

of the advantage resulting from the division of labour. As in the

view I have taken of the question, the most important and

influential cause has been altogether unnoticed, I shall restate

those principles in the words of Adam Smith:

 

“The great increase in the quantity of work, which, in consequence

of the division of labour, the same number of people are capable

of performing, is owing to three different circumstances: first,

to the increase of dexterity in every particular workman;

secondly, to the saving of time, which is commonly lost in

passing from one species of work to another; and, lastly, to the

invention of a great number of machines which facilitate and

abridge labour, and enable one man to do the work of many.”

 

Now, although all these are important causes, and each has

its influence on the result; yet it appears to me, that any

explanation of the cheapness of manufactured articles, as

consequent upon the division of labour, would be incomplete if

the following principle were omitted to be stated.

 

That the master manufacturer, by dividing the work to be

executed into different processes, each requiring different

degrees of skill or of force, can purchase exactly that precise

quantity of both which is necessary for each process; whereas, if

the whole work were executed by one workman, that person must

possess sufficient skill to perform the most difficult, and

sufficient strength to execute the most laborious, of the

operations into which the art is divided.(1*)

 

227. As the clear apprehension of this principle, upon which

a great part of the economy arising from the division of labour

depends, is of considerable importance, it may be desirable to

point out its precise and numerical application in some specific

manufacture. The art of making needles is, perhaps, that which I

should have selected for this illustration, as comprehending a

very large number of processes remarkably different in their

nature; but the less difficult art of pinmaking, has some claim

to attention, from its having been used by Adam Smith; and I am

confirmed in the choice of it, by the circumstance of our

possessing a very accurate and minute description of that art, as

practised in France above half a century ago.

 

228. Pinmaking. In the manufacture of pins in England the

following processes are employed:

 

1. Wire-drawing. (a) The brass wire used for making pins is

purchased by the manufacturer in coils of about twenty-two inches

in diameter, each weighing about thirty-six pounds. (b) The coils

are wound off into smaller ones of about six inches in diameter,

and between one and two pounds’ weight. (c) The diameter of this

wire is now reduced, by drawing it repeatedly through holes in

steel plates, until it becomes of the size required for the sort

of pins intended to be made. During this process the wire is

hardened, and to prevent its breaking, it must be annealed two or

three times, according to the diminution of diameter required.

(d) The coils are then soaked in sulphuric acid, largely diluted

with water, in order to clean them, and are then beaten on stone,

for the purpose of removing any oxidated coating which may adhere

to them. These operations are usually performed by men, who draw

and clean from thirty to thirty-six pounds of wire a day. They

are paid at the rate of five farthings per pound, and generally

earn about 3s. 6d. per day.

 

M. Perronnet made some experiments on the extension the wire

undergoes in passing through each hole: he took a piece of thick

Swedish brass wire, and found

 

Feet Inches

Its length to be before drawing 3 8

After passing the first hole 5 5

second hole 7 2

third hole 7 8

 

It was now annealed, and the length became

 

After passing the fourth hole 10 8

fifth hole 13 1

sixth hole 16 8

And finally, after passing through six other holes 144 0

 

The holes through which the wire was drawn were not, in this

experiment, of regularly decreasing diameter: it is extremely

difficult to make such holes, and still more to preserve them in

their original dimensions.

 

229. 2. Straightening the wire. The coil of wire now passes

into the hands of a woman, assisted by a boy or girl. A few

nails, or iron pins, not quite in a line, are fixed into one end

of a wooden table about twenty feet in length; the end of the

wire is passed alternately between these nails, and is then

pulled