I hardly know whether I do well in writing to you.  If such trouble befell me there are very few people in the world from whom I could bear even sympathy—­but you would be one of them, and therefore I hope that you will forgive a condolence which will reach you so late as to disturb rather than soothe, for the sake of the hearty affection which dictates it.

My wife has told me of the very kind letter you wrote her.  I was thoroughly broken down when I left England, and did not get much better until I fell into the utter and absolute laziness of dahabieh life.  A month of that has completely set me up.  I am as well as ever; and though very grateful to Old Nile for all that he has done for me—­not least for a whole universe of new thoughts and pictures of life—­I begin to feel strongly

    ‘the need of a world of men for me.’

But I am not going to overwork myself again.  Pray make my kindest remembrances to Mrs. Arnold, and believe me, always yours very faithfully,

T.H.  Huxley.

[Leaving Assouan on March 3, and Cairo on the 18th, he returned by way of Messina to Naples, taking a day at Catania to look at Etna.  At Naples he found his friend Dohrn was absent, and his place as host was filled by his father.  Vesuvius was ascended, Pozzuoli and Pompeii visited, and two days spent in Rome.]

Hotel de Grande Bretagne, Naples, March 31, 1872.

My dear Tyndall,

Your very welcome letter did not reach me until the 18th of March, when I returned to Cairo from my expedition to Assouan.  Like Johnny Gilpin, I “little thought when I set out, of running such a rig”; but while at Cairo I fell in with Ossory of the Athenaeum, and a very pleasant fellow, Charles Ellis, who had taken a dahabieh, and were about to start up the Nile.  They invited me to take possession of a vacant third cabin, and I accepted their hospitality, with the intention of going as far as Thebes and returning on my own hook.  But when we got to Thebes I found there was no getting away again without much more exposure and fatigue than I felt justified in facing just then, and as my friends showed no disposition to be rid of me, I stuck to the boat, and only left them on the return voyage at Rodu, which is the terminus of the railway, about 150 miles from Cairo.

We had an unusually quick journey, as I was little more than a month away from Cairo, and as my companions made themselves very agreeable, it was very pleasant.  I was not particularly well at first, but by degrees the utter rest of this “always afternoon” sort of life did its work, and I am as well and vigorous now as ever I was in my life.