At an early period his friend Wedgwood had strongly urged upon Watt that he should work less with his own head and hands, and more through the heads and hands of others.[287] Watt’s brain was too active for his body, and needed rest; but rest he would not take, and persisted in executing all the plans of the new engines himself. Thus in his fragile, nervous, dyspeptic state, every increase of business was to him increase of brain-work and increase of pain; until it seemed as if not only his health, but the very foundations of his reason must give way. At the very time when Soho was beginning to bask in the sunshine of prosperity, and the financial troubles of the firm seemed coming to an end, Watt wrote the following profoundly melancholy letter to a friend:-- “I have been effete and listless, neither daring to face business, nor capable of it, my head and memory failing me much; my stable of hobby-horses pulled down, and the horses given to the dogs for carrion.... I have had serious thoughts of laying down the burden I find myself unable to carry, and perhaps, if other sentiments had not been stronger, should have thought of throwing off the mortal coil; but, if matters do not grow worse, I may perhaps stagger on. Solomon said that in the increase of knowledge there is increase of sorrow; if he had substituted _business_ for knowledge, it would have been perfectly true.”[288] [287] “Your mind, my friend, is too active, too powerful for your body, and harasses it beyond its bearing. If this was the case with any other machine under your direction, except that in whose regulation your friends take so much interest, you would soon find out a remedy. For the present permit me to advise a more ample use of _the oil of delegation_ through your whole machinery, and I am persuaded you will soon find some salutary effects from this application. Seriously, I shall conclude in saying to you what Dr. Fothergill desired me to say to Brindley--‘Spare your machine a little, or like others under your direction, it will wear out the sooner by hard and constant usage.’”--Josiah Wedgwood to Watt, December 10, 1782. [288] Watt to his brother-in-law, Gilbert Hamilton, Glasgow, June 18, 1786.