Folios 110-111: AAL to ADM
Ockham
Monday. 6th July
Dear Mr De Morgan. Since dispatching my letter
yesterday, I remember that I have not even
quite fully & correctly stated the whole points
of difference ['between' inserted] \(\int\sqrt{a^2-x^2}x^{n-2}dx\) and \(\int\sqrt{v}d2u\) . I
think I stated that \(\int\sqrt{a^2-x^2}x^{n-2}dx=\int\sqrt{v}d2u.\frac{-1}{x}\),
that in other words the 1st side differs from
\( \int\sqrt{v}d2u\) in containing a factor \(\left(-\frac{1}{x}\right)\) . But
it differs also in containing \(dx\) as well,
which in writing yesterday I omitted I believe
to notice. So that \(\int\sqrt{a^2-x^2}x^{n-2}dx=\int\sqrt{v}d2u.\frac{(-1)}{x}.dx\)
or the 1st side differs from \(\int\sqrt{v}d2u\) in
containing \(-\frac{1}{x}.dx\) . Is not this what I ought
to have stated? Or is there still any confusion?
I also wish to observe upon
what I wrote on Friday as to the application
of the Differential & Integral Calculus to \(\frac{gt^2}{2}\),
[110v] that I am aware this formula ['\((e=\frac{gt^2}{2}\) ' inserted] can be
derived from \(V=gt\), by the simple Theory of
algebraical proportion; but that I was anxious
to know how it is derived in the other way.
I will with your leave ['(which I do not wait for)' inserted], send you
my paper making it out on the doctrine of
Proportions.
You must tell me if I presume too much
on your kindness to me. I am so
engaged at present with my mathematical
& scientific plans & pursuits that I can
think of little else; & perhaps may be a
plague & bore to my friends about [something crossed out] these
subjects; for after my interruption from
Paris & London pursuits & occupations, my
whole heart is with my renewed studies; &
every minutia even is a matter of the greatest
interest.
Believe me
Yours most truly
A. A. Lovelace
[111r] [something crossed out] You ['will receive' inserted] two papers on \(e=\frac{gt^2}{2}\) tomorrow
evening, or Weddy . One of them is to show the
absurdity of the supposition that the spaces might
be as the velocities; ['& that' inserted] on merely abstract grounds
it could not be.
About this document
All Ada Lovelace manuscript images on the
Clay Mathematics Institute website are
© 2015 The Lovelace Byron Papers,
reproduced by permission of
Pollinger Limited. To re-use them in
any form, please apply to
katyloffman@pollingerltd.com.
The LaTeX transcripts of the letters
were made by Christopher Hollings
(christopher.hollings@maths.ox.ac.uk).
Their re-use in any form requires his
permission, and is subject to the
rights reserved to the owner of
The Lovelace Byron Papers.
Bodleian Library, Oxford, UK
Dep. Lovelace Byron