[14] This letter was intercepted by the British ministry; Dr. F. had preserved a copy of it, which was afterward transmitted to Lord Kames; but the wisdom that composed and conveyed it was thrown away upon the men at that time in power.
"London, February 21, 1769.
"My dear Friend,
"I received your excellent paper on the preferable use of oxen in agriculture, and have put it in the way of being communicated to the public here. I have observed in America that the farmers are more thriving in those parts of the country where horned cattle are used, than in those where the labour is done by horses. The latter are said to require twice the quantity of land to maintain them and, after all, are not good to eat—at least we don't think them so. Here is a waste of land that might afford subsistence for so many of the human species. Perhaps it was for this reason that the Hebrew lawgiver, having promised that the children of Israel should be as numerous as the sands of the sea, not only took care to secure the health of individuals by regulating their diet, that they might be better fitted for producing children, but also forbid their using horses, as those animals would lessen the quantity of subsistence for man. Thus we find, when they took any horses from their enemies, they destroyed them; and in the commandments, where the labour of the ox and ass is mentioned, and forbidden on the Sabbath, there is no mention of the horse, probably because they were to have none. And by the great armies suddenly raised in that small territory they inhabited, it appears to have been very full of people.[15]
"Food is always necessary to all, and much the greatest part of the labour of mankind is employed in raising provisions for the mouth. Is not this kind of labour, then, the fittest to be the standard by which to measure the values of all other labour, and, consequently, of all other things whose value depends on the labour of making or procuring them? may not even gold and silver be thus valued? If the labour of the farmer, in producing a bushel of wheat, be equal to the labour of the miner in producing an ounce of silver, will not the bushel of wheat just measure the value of the ounce of silver. The miner must eat; the farmer, indeed, can live without the ounce of silver, and so, perhaps, will have some advantage in settling the price. But these discussions I leave to you, as being more able to manage them: only, I will send you a little scrap I wrote some time since on the laws prohibiting foreign commodities.
"I congratulate you on your election as president of your Edinburgh Society. I think I formerly took notice to you in conversation, that I thought there had been some similarity in our fortunes and the circumstances of our lives. This is a fresh instance, for by letters just received I find that I was about the same time chosen President of our American Philosophical Society, established at Philadelphia.[16]