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700 ‘TRANSLATOR’S NOTES TO M. MENABREA’S MEMOIR 
sults we think we could now hint at, had we the space; and others, 
which it may not yet be possible to foresee, but which would be brought 
forth by the daily increasing requirements of science, and by a more 
intimate practical acquaintance with the powers of the engine, were it 
in actual existence. 
On general grounds, both of an @ priori description as well as those 
founded on the scientific history and experience of mankind, we see 
strong presumptions that such would be the case, Nevertheless all 
will probably concur in feeling that the completion of the Difference 
Engine would be far preferable to the non-completion of any calculating 
engine at all. With whomsoever or wheresoever may rest the present 
causes of difficulty that apparently exist towards either the completion 
of the old engine, or the commencement of the new one, we trust they 
will not ultimately result in this generation’s being acquainted with 
these inventions through the medium of pen, ink and paper merely ; 
and still more do we hope, that for the honour of our country’s reputa- 
tion in the future pages of history, these causes will not lead to the 
completion of the undertaking by some other nation or government. 
This could not but be matter of just regret ; and equally so, whether 
the obstacles may have originated in private interests and feelings, in 
considerations of a more public description, or in causes combining the 
nature of both such solutions. 
We refer the reader to the ‘ Edinburgh Review’ of July 1834, fora 
very able account of the Difference Engine. The writer of the article 
we allude to, has selected as his prominent matter for exposition, a 
wholly different view of the subject from that which M. Menabrea 
has chosen. The former chiefly treats it under its mechanical aspect, 
entering but slightly into the mathematical principles of which that 
engine is the representative, but giving, in considerable length, many 
details of the mechanism and contrivances by means of which it tabu- 
lates the various orders of differences. M.Menabrea, on the con- 
trary,exclusively developes the analytical view; taking it for granted that, 
mechanism is able to perform certain processes, but without attempting 
to explain how; and devoting his whole attention to explanations and 
illustrations of the manner in which analytical laws can be so arranged 
and combined as to bring every branch of that vast subject within the 
grasp of the assumed powers of mechanism, It is obvious that, in the 
invention of a calculating engine, these two branches of the subject are 
equally essential fields of investigation, and that on their mutual ad- 
justment, one to the other, must depend all success. They must be 
made to meet each other, so that the weak points in the powers of 
either department may be compensated by the strong points in those of 
the other. They are indissolubly connected, though so different in 
their intrinsic nature that perhaps the same mind might not be likely to 
prove equally profound or successful in both. We know those who 
doubt whether the powers of mechanism will in practice prove ade- 
quate in all respects to the demands made upon them in the working 
of such complicated trains of machinery as those of the above engines, 
and whoapprehend thatunforeseen practical difficulties and disturbances 
will arise in the way of accuracy and of facility of operation. The 
Difference Engine, however, appears to us to be in a great measure an 
answer to these doubts. It is complete as far as it goes, and it does work 
with all the anticipated success, The Analytical Engine, far from bes 
