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for the Conway Tubular Bridge while under construction； in 1848； were
greatly hampered by combinations amongst the workmen； and they
despaired of being able to finish the girders within the time
specified in the contract。 The punching of the iron plates by hand
was a tedious and expensive as well as an inaccurate process； and the
work was proceeding so slowly that the contractors found it
absolutely necessary to adopt some new method of punching if they
were to finish the work in time。 In their emergency they appealed to
Mr。 Roberts； and endeavoured to persuade him to take the matter up。
He at length consented to do so； and evolved the machine in question
during his evening's leisurefor the most part while quietly sipping
his tea。 The machine was produced； the contractors were enabled to
proceed with the punching of the plates independent of the refractory
men； and the work was executed with a despatch； accuracy； and
excellence that would not otherwise have been possible。 Only a few
years since Mr。 Roberts added a useful companion to the Jacquard
punching machine； in his combined self…acting machine for shearing
iron and punching both webs of angle or T iron simultaneously to any
required pitch； though this machine； like others which have proceeded
from his fertile brain； is ahead even of this fast…manufacturing age；
and has not yet come into general use； but is certain to do so before
many years have elapsed。
These inventions were surely enough for one man to have accomplished；
but we have not yet done。 The mere enumeration of his other
inventions would occupy several pages。 We shall merely allude to a
few of them。 One was his Turret Clock； for which he obtained the
medal at the Great Exhibition of 1851。 Another was his Prize
Electro…Magnet of 1845。 When this subject was first mentioned to him；
he said he did not know anything of the theory or practice of
electro…magnetism； but he would try and find out。 The result of his
trying was that he won the prize for the most powerful
electro…magnet： one is placed in the museum at Peel Park； Manchester；
and another with the Scottish Society of Arts； Edinburgh。 In 1846 he
perfected an American invention for making cigars by machinery；
enabling a boy； working one of his cigar…engines； to make as many as
5000 in a day。 In 1852 he patented improvements in the construction；
propelling； and equipment of steamships； which have； we believe； been
adopted to a certain extent by the Admiralty； and a few years later；
in 1855； we find him presenting the Secretary of War with plans of
elongated rifle projectiles to be used in smooth…bore ordnance with a
view to utilize the old…pattern gun。 His head； like many inventors of
the time； being full of the mechanics of war； he went so far as to
wait upon Louis Napoleon； and laid before him a plan by which
Sebastopol was to be blown down。 In short； upon whatever subject he
turned his mind； he left the impress of his inventive faculty。 If it
was imperfect； he improved it； if incapable of improvement； and
impracticable； he invented something entirely new； superseding it
altogether。 But with all his inventive genius； in the exercise of
which Mr。 Roberts has so largely added to the productive power of the
country； we regret to say that he is not gifted with the commercial
faculty。 He has helped others in their difficulties； but forgotten
himself。 Many have profited by his inventions； without even
acknowledging the obligations which they owed to him。 They have used
his brains and copied his tools； and the 〃sucked orange〃 is all but
forgotten。 There may have been a want of worldly wisdom on his part；
but it is lamentable to think that one of the most prolific and
useful inventors of his time should in his old age be left to fight
with poverty。
Mr。 Whitworth is another of the first…class tool…makers of Manchester
who has turned to excellent account his training in the workshops of
Maudslay and Clement。 He has carried fully out the system of
uniformity in Screw Threads which they initiated； and he has still
further improved the mechanism of the planing machine； enabling it to
work both backwards and forwards by means of a screw and roller
motion。 His 〃Jim Crow Machine；〃 so called from its peculiar motion in
reversing itself and working both ways； is an extremely beautiful
tool； adapted alike for horizontal； vertical； or angular motions。 The
minute accuracy of Mr。 Whitworth's machines is not the least of their
merits； and nothing will satisfy him short of perfect truth。 At the
meeting of the Institute of Mechanical Engineers at Glasgow in 1856
he read a paper on the essential importance of possessing a true
plane as a standard of reference in mechanical constructions； and he
described elaborately the true method of securing it；namely； by
scraping； instead of by the ordinary process of grinding。 At the same
meeting he exhibited a machine of his invention by which he stated
that a difference of the millionth part of an inch in length could at
once be detected。 He also there urged his favourite idea of
uniformity； and proper gradations of size of parts； in all the
various branches of the mechanical arts； as a chief means towards
economy of productiona principle； as he showed； capable of very
extensive application。 To show the progress of tools and machinery in
his own time； Mr。 Whitworth cited the fact that thirty years since
the cost of labour for making a surface of cast…iron trueone of the
most important operations in mechanicsby chipping and filing by the
hand； was 12s。 a square foot； whereas it is now done by the planing
machine at a cost for labour of less than a penny。 Then in machinery；
pieces of 74 reed printing…cotton cloth of 29 yards each could not be
produced at less cost than 30s。 6d。 per piece； whereas the same
description is now sold for 3s。 9d。 Mr。 Whitworth has been among the
most effective workers in this field of improvement； his tools taking
the first place in point of speed； accuracy； and finish of work； in
which respects they challenge competition with the world。 Mr。
Whitworth has of late years been applying himself with his accustomed
ardour to the development of the powers of rifled guns and
projectiles；a branch of mechanical science in which he confessedly
holds a foremost place； and in perfecting which he is still occupied。
CHAPTER XV。
JAMES NASMYTH。
〃By Hammer and Hand
All Arts doth stand。〃
Hammermen's Motto。
The founder Of the Scotch family of Naesmyth is said to have derived
his name from the following circumstance。 In the course of the feuds
which raged for some time between the Scotch kings and their powerful
subjects the Earls of Douglas； a rencontre took place one day on the
outskirts of a Border village； when the king's adherents were
worsted。 One of them took refuge in the village smithy； where；
hastily disguising h