From Mary Somerville   [20 October 1829]

Oct[ober] 1829

My dear Sir

If you will have the goodness to send me the last 8 or 10 sheets of my MMS together with the one I sent you the other day I think I can both make an improvement and save you some trouble. Mr Richards comes to town on Thursday morn and will take charge of them with every kind wish to Mrs Herschel believe me truly y[ou]rs

M. Somerville

Monday

MS Dep. c. 370 MSH–3 310

My dear Madam,

I have just got your note with the integration of the equation in terms of $r$ by indeterminate coefficients at present I see nothing to object against it, but shall read it more carefully with the context.

I have at lengths sent an end to a work which (though not much in itself) yet gave me a great deal of trouble, much more so than when I entered on it I could have imagined possible. It is an essay on sound as a companion to the work on Light of which you have a copy, as I mean you shall of its fellow — as soon as it appears. [illegible] have now in great measure completed the more troublesome part of the reduction of my sweeps, which hung upon me like an incubus, and stung my conscience whenever I thought of it — a little energy however has sufficed to see me nearly free from the worst of bondages — astronomical reductions accumulated on hand! The first result will be speedily I hope in your hands in the shape of a catalogue of about a thousand or 1500 more double stars [illegible] measured with the 20 feet, since June 1828.

I shall now be able to bestow my undivided attention on your work which hitherto I have found it impossible to do, though I have often begun it and as often been forced to desist. To you who knows what it is to write such a work I need offer little excuse for the delay. As it is not to be written currente calamo so it is not to be read by one who runs and reads. Indeed to be very candid with you, I cannot pretend to read the whole of it — there will be parts, very large ones, on which I cannot give an opinion.

You and Dr S will be happy to hear that my mother continues steadily [illegible] in health. Her constitution is wonderfully vigorous, and though it has maintained a fearful struggle I yet trust that much of her strength remains unsubdued. I have taken a very nice comfortable house for her in Windsor and in some ten days or a fortnight I hope once more to do have her near me. She & Mrs Herschel join in kind regards to yourself & Dr S and I remain

Dear Madam

yours very truly

J F W Herschel