3-15-26. George Howard Darwin to H. Poincaré
Dear Monsieur Poincaré,
Since I last wrote I have continued to work at my subject & have met with unexpected success. The most troublesome integrals disappear automatically and a number of others can be obtained rigorously without elliptic integrals. I have now arranged the work in a very convenient form & have started a professional computer at the integrals. The work will not be very long. It would be tedious though not difficult to express them all in and .
I find also that, by proper interpretation of the symbols and change of third harmonic to second, this result is applicable to this initial Jacobian considered as a deformation of an ellipsoid of revolution. I expect to have the result in a day or two, and if it is correct it seems to me absolutely impossible that I can be wrong in the problem of the pear.
It has been a very troublesome piece of analysis. I found it convenient to join part of my to , then to join the other part to ; to join with part of . The remaining part of is deducible by means of . All this was not discovered until I had made many trials & failures.
I look forward to your letter with much interest.
G. H. Darwin
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