'It seems amazing that one couldn't manage to make more productive use of the time': a reflective letter, on his style of life after his wife's death, on his latest discoveries, the pleasures and quirks of life in the United States, and a memory of his old days with Besso.

Besso had evidently written to his old friend to express condolences on the death of Elsa Einstein (on 20 December 1936). 'I am happy that this sad circumstance gives me a reason once again to send greetings to you. I now live like an old confirmed bachelor [Hagestolz] in a pretty house surrounded by greenery and slave away on my problems, still with the old enjoyment. The fine thing here is that I can collaborate with young colleagues. It's striking that in my long life I have collaborated exclusively with Jews'.

As regards his latest discoveries: 'We have after long efforts discovered that the equations of relativity with a direct relativistic adaptation of Maxwell's equations do not permit a solution of the problem of material particles. I have however recently discovered that there is a very natural variation of Maxwell's theory in which potentials do not appear in the principle of variation. I am curious to discover whether we can reach our goal in this way'.

Work is, in a sense, something of a refuge, as is his old pastime of sailing: 'It is good that one has become so closely attached to one's hobby horse that one becomes somewhat detached from the outside world; for otherwise it would be hard to retain any pleasure in this life. In a few days I shall return to the coast in order to refresh the old Adam with some sailing during the summer months. There are wonderful natural beauties in this country'. He remarks that America offers a chance to anyone provided they master a practical trade ('einen Schusterberuf'): for more eccentric figures ('four-leaf clovers') like himself, it is quite otherwise.

The letter ends with memories of youthful days shared with Besso at the Swiss Federal Patent Office: 'I still often think, and with pleasure, of our old times in the patent office and I simply cannot grasp that I shall soon be 30 years distant from those days. That makes roughly 10⁹ seconds, after all, and it seems amazing that one couldn't manage to make more productive use of that time'.