M E C H A N I 
thus man Is capable of every thing, or of nothing, as his 
pewers are adequate or not to this bringing together or 
feparating.” 
Sometimes we are ignorant of the origin of a mechanical 
art, or are but imperfectly acquainted with its progrefs: 
thefe are the natural confequences of the contempt in 
which artifans have been often held, and particularly 
among the molt warlike nations. In thefe cales, we mult 
call in the aid of philofophy, and fet out upon l'orne pro¬ 
bable hypothefis, from fome lucky accident or hint, and 
thence explain how the art might probably have proceeded, 
till we come to the era of certainty. We (hall illuftrate 
this idea by an example drawn rather from the mechanical 
arts, which are lefs known, than from the liberal arts, 
which have been exhibited to the world in every point of 
view. Suppofe we were unacquainted with the origin and 
progrefs of glafs-makmg and paper-making, how would a 
philofopher proceed in writing the hiltory of thofe arts ? 
He would fuppofe, that a bit of linen cloth had fallen ac¬ 
cidentally into a veffel of water, where it had remained 
long enough to be diffolved ; and that, on emptying the 
veffel, inflead of finding the piece of linen at the bottom, 
nothing had been found but a kind of fediment; the nature 
of which it would have been very difficult to analyfe or de¬ 
fine, were it not that fome filaments or threads remained, 
indicating that the original matter compofing that fedi- 
ment had formerly exilted in the form of linen.—As to 
glafs, he would fuppofe that the fir It folid habitations of 
men were conftruded of baked earth, or bricks ; now, it 
is impoffible to burn bricks with a lirong fire without vi- 
trefying fome part: in this way glafs firlt made its ap¬ 
pearance ; but what an immenfe diftance between that 
dirty greenifh fcale and the pure trnnfparent matter of our 
looking-glaffes! This however, or fome Inch accident, 
would be the point whence a philofopher would fet out in 
ascertaining the origin and progrefs of making glafs. And 
indeed, by fuel) means as thefe, the progrefs of an art 
would be detailed in a more itfeful and inftrudtive manner 
than by its true hiltory, fuppoling that to be known. The 
obflacles to be overcome would be prefented in the molt 
natural order ; a fynthetic explanation of the fucceffive 
operations of the art would Amplify it to the molt ordi¬ 
nary capacity, and put artifans in a way of continual im¬ 
provement. 
As to the order which (hould be followed in fuch a hif- 
tory of the arts, the moft advantageous would be to carry 
back the arts to the productions of nature. An exafl enu¬ 
meration of thefe productions would give birth to many 
arts as yet unknown ; many others might arife from exa¬ 
mining the fame production under every different form 
and circumftance. But fuch a treatife on the arts can be 
the work of no common genius ; great knowledge of na¬ 
ture is required, and valt powers of reafoning from ap¬ 
pearances and effects. Yet the reader will bear in mind, 
that what cannot be achieved by one man, may be accorn- 
pliflied by the joint labours of a fociety or company. A 
great philofopher has obferved, that the hiltory of nature 
is incomplete without that of the arts ; and he exhorts 
naturalifts to crown their labours in the vegetable, mineral, 
and animal, kingdoms, by experiments in the mechanical 
arts, the knowledge and praCtice of which is of the utnioft 
importance to true philofophy. Thefe are not vain ideas ; 
they are the dictates of philofophy, reafon, and experience; 
and whoever would controvert them, feeks to narrow the 
fphere of our attainments, and to difeourage the exertions 
of genius. 
We owe many curious difeoveries to chance; and (hall 
we fuppofe that chance may not aid us Kill farther, when 
we add ourown efforts to its caprices, and follow up our 
refearches with order and method ? Since we already pof- 
fefs fecrets not expefted formerly, if we may be permitted 
to draw conjectures from what has happened, why may we 
not hereafter difeover fecrets which at prefent we have no 
sdea of ? Had it been faid, a few ages ago, to perfons who 
meafure the poffibility of things by the limits of their own 
Vol.XIV. No. 999. 
CAL ART «J7 
genius, and who can imagine nothing beyond what they 
known, that a powder or dult would be compounded, 
which would fplit rocks, throw down the ftrongeft walls 
at a vaft diftance ; and of which if a few pounds were bu¬ 
ried deep in the earth, it would (hake it, make its way into 
open air through enormolis maffes of earth and (tones, 
and perhaps form fuch a gulf as might fwallow many 
houfes—fuch perfons no doubt would prefently have com¬ 
pared thefe effeHs with the agency of wheels, pulleys, le¬ 
vers, weights,and other machines then known; and would 
have pronounced that fuch a powder never could exift; 
and that nothing but thunder,or the power that produces 
earthquakes, which is not to he imitated by man, would 
ever be capable of working fuch dreadful effects. What 
would fuel) people, in any age, have faid of the propofed 
invention, firlt executed in London, of a machine for raif- 
ing water by means of fire, and that fuch a machine (hould 
even become ufefulin navigating veffels ? If we had none 
but fuch perfons to judge of inventions, we fliould per¬ 
form neither great things r.or fmall ones. What more¬ 
over ought to excite us to indultry and attention, is the 
confideration how many ages patted away before men per¬ 
ceived many ufeful things which they had, as it were, 
before their eyes; fuch as the art of printing and of en¬ 
graving. When difeoveries or improvements are to ba 
(ought for, man too often miftrufts his own powers, and 
is diftieartened at the very difficulties he raifes hirnfelfj 
when they are attained, he wonders that it was neceffary 
tol'eek fo long ; and then he laments his own weaknefs! 
With refpecl to the manner of deferibing certain of the 
mechanical arts, it is to be obferved, that a complex ma¬ 
chine is fometimes ufed to produce an effedt apparently 
very Ample ; and fometimes a Ample machine (eems to 
produce a complicated effedt. In the former cafe, the ef¬ 
fect to be produced being eafily underltood, fo that a know¬ 
ledge of it cannot confufe the judgment nor burthen the 
memory, this effedt (hould be firlt explained, and after¬ 
wards (hould come a defeription of the machine. In the 
latter cafe, on the contrary, it is better to proceed from 
an account of the machine to a knowledge of its effect. 
The adtion of a clock or watch is to divide time into 
equal parts, by means of an index which moves uniform¬ 
ly and very (lowly round a plain farface properly marked. 
If, therefore, I were to (how a watch to a perlon unac¬ 
quainted with fuch a machine, I (hould firtt point out the 
effedt, which is fimple, and then proceed to explain the 
complicated mechanifm. But I (hould follow a different 
method, were I to be aiked the nature of cloth, drugget, 
velvet, or fatin : I (hould begin by deferibing the trades 
which produce thofe compound textures. A clearexpla- 
nation of the machine makes the effedt quickly underltood, 
which perhaps would be utterly impoffible without it. For 
inltance, let any one endeavour correctly to define what 
gauze is, without giving fome previous knowledge of the 
machine by which it is made. 
It will eafily be granted, that there are few artifans ta 
whom the elements of mathematics are not necettary ; but 
ifis a paradox of which the truth is not immediately evi¬ 
dent, that thofe very principles would miflead them upon 
many occafions, if phyfical or natural knowledge did not 
correct the principles in the practice: a knowledge of 
places, of pofitions, of materials, their qualities, eialticity, 
ftiffnels ; of fridtion, confiftence, ftrength ; the effects of 
air, water, cold, heat, drynefs, &c. It is clear that the ele¬ 
ments of the geometry of the fchools are but the molt Am¬ 
ple and lead: complicated of thole belonging to the geome¬ 
try of the workshops, There is not in nature a lever fuck 
as Varignon fuppofes in his propofitions ; there is not a le¬ 
ver in nature every one of whofe qualities or conditions can 
be fubjedted to calculation. So that a man who poffeffes 
only the intellectual geometry is generally very unlkil- 
ful; while an artitt: who knows the practical geometry 
only can be but a confined workman. But it appears 
from experience, that an artitt: can better do without the 
ichool-geometry, than any man without a certain know- 
