uld not sleep for thinking about it. In the morning he
strolled up Primrose Hill, and returned home still muttering to himself
about "that roof." "What," said his wife to him, "are you thinking of
Galloway's roof?" "Yes," said he. "Then you have seen the papers?"
"No--what about them?" "Galloway's roof has fallen in this morning,
and killed eight or ten of the men!" Keir immediately went to bed, and
slept soundly till next morning.

[2] See more particularly The Transactions of the Society for the
Encouragement of Arts, vol. xxxiii. (1817), at pp. 74, 157, 160, 175,
208 (an admirable drawing; of Mr. James Allen's Theodolite); vol.
xxxvi. (1818), pp. 28, 176 (a series of remarkable illustrations of Mr.
Clement's own invention of an Instrument for Drawing Ellipses); vol.
xliii. (1825), containing an illustration of the Drawing Table invented
by him for large drawings; vol. xlvi. (1828), containing a series of
elaborate illustrations of his Prize Turning Lathe; and xlviii. 1829,
containing illustrations of his Self-adjusting Double Driver Centre
Chuck.

[3] Transactions of the Society for the Encouragement of Arts, vol.
xlix. p.157.

[4] A complete account of the calculating machine, as well as of an
analytical engine afterwards contrived by Mr. Babbage, of still greater
power than the other, will be found in the Bibliotheque Universelle de
Geneve, of which a translation into English, with copious original
notes, by the late Lady Lovelace, daughter of Lord Byron, was published
in the 3rd vol. of Taylor's Scientific Memoirs (London, 1843). A
history of the machine, and of the circumstances connected with its
construction, will also be found in Weld's History of the Royal
Society, vol. ii. 369-391. It remains to be added, that the perusal by
Messrs. Scheutz of Stockholm of Dr. Lardner's account of Mr. Babbage's
engine in the Edinburgh Review, led those clever mechanics to enter
upon the scheme of constructing and completing it, and the result is,
that their machine not only calculates the tables, but prints the
results. It took them nearly twenty years to perfect it, but when
completed the machine seemed to be almost capable of thinking. The
original was exhibited at the Paris Exhibition of 1855. A copy of it
has since been secured by the English government at a cost of 1200L.,
and it is now busily employed at Somerset House in working out annuity
and other tables for the Registrar-General. The copy was constr