MRS. SOMERVILLE TO W. GREIG, ESQ.
Rome, May 28th, 1845.
I don't know why I have so long delayed writing to you. I rather think it is because we have been living so quiet a life, one day so precisely similar to the preceding, that there has been nothing worth writing about. This is our first really summer-like day, and splendid it is; but we are sitting in a kind of twilight. The only means of keeping the rooms cool is by keeping the house dark and shutting out the external air, and then in the evening we have a delightful walk; the country is splendid, the Campagna one sheet of deep verdure and flowers of every kind in abundance. We generally have six or seven large nosegays in the room; we have only to go to some of the neighbouring villas and gather them. Most of the English are gone; people make a great mistake in not remaining during the hot weather, this is the time for enjoyment. We are busy all the morning, and in the afternoon we take our book or drawing materials and sit on the grass in some of the lovely villas for hours; then we come home to tea, and are glad to see anyone who will come in for an hour or two. We have had a son of Mr. Babbage here. He is employed in making the railway that is to go from Genoa to Milan, and he was travelling with eight other Englishmen who came to make arrangements for covering Italy with a network of these iron roads, connecting all the great cities and also the two seas from Venice to Milan and Genoa and from Ancona by Rome to Civita Vecchia. However the Pope is opposed to the latter part, but they say the cardinals and people wish it so much that he will at last consent.... Many thanks for the Vestiges, &c. I think it a powerful production, and was highly pleased with it, but I can easily see that it will offend in some quarters; however it should be remembered that there has been as much opposition to the true system of astronomy and to geological facts as there can be to this. At all events free and open discussion of all natural and moral phenomena must lead to truth at last. Is Babbage the author? I rather think he would not be so careful in concealing his name....
My mother made some curious experiments upon the effect of the solar spectrum on juices of plants and other substances, of which she sent an account to Sir John Herschel, who answered telling her that he had communicated her account of her experiments to the Royal Society.
SIR JOHN HERSCHEL TO MRS. SOMERVILLE.
Collingwood, November 21st, 1845.
I cannot express to you the pleasure I experienced from the receipt of your letter and the perusal of the elegant experiments it relates, which appear to me of the highest interest and show (what I always suspected), that there is a world of wonders awaiting disclosure in the solar spectrum, and that influences widely differing from either light, heat or colour are transmitted to us from our central luminary, which are mainly instrumental in evolving and maturing the splendid hues of the vegetable creation and elaborating the juices to which they owe their beauty and their vitality. I think it certain that heat goes for something in evaporating your liquids and thereby causing some of your phenomena; but there is a difference of quality as well as of quantity of heat brought into view which renders it susceptible of analysis by the coloured juices so that in certain parts of the spectrum it is retained and fixed, in others reflected according as the nature of the tint favours the one or the other. Pray go on with these delightful experiments. I wish you could save yourself the fatigue of watching and directing your sunbeam by a clock work. If I were at your elbow I could rig you out a heliotrope quite sufficient with the aid of any common wooden clock.... Now I am going to take a liberty (but not till after duly consulting Mr. Greig with whose approbation I act, and you are not to gainsay our proceedings) and that is to communicate your results in the form of "an extract of a letter" to myself—to the Royal Society. You may be very sure that I would not do this if I thought that the experiments were not intrinsically quite deserving to be recorded in the pages of the Phil. Trans. and if I were not sure that they will lead to a vast field of curious and beautiful research; and as you have already once contributed to the Society, (on a subject connected with the spectrum and the sunbeam) this will, I trust, not appear in your eyes in a formidable or a repulsive light, and it will be a great matter of congratulation to us all to know that these subjects continue to engage your attention, and that you can turn your residence in that sunny clime to such admirable account. So do not call upon me to retract (for before you get this the papers will be in the secretary's hands).
I am here nearly as much out of the full stream of scientific matters as you at Rome. We had a full and very satisfactory meeting at Cambridge of the British Association, with a full attendance of continental magnetists and meteorologists, and within these few days I have learned that our Government meant to grant all our requests and continue the magnetic and meteorological observations. Humboldt has sent me his Cosmos (Vol. I.), which is good, all but the first 60 pages, which are occupied in telling his readers what his book is not to be. Dr. Whewell has just published another book on the Principles of Morals, and also another on education, in which he cries up the geometrical processes in preference to analysis....