but these, it was obvious, would of themselves fall with the trade.  A third was, excessive labour joined with improper food; and a fourth was, the extreme dissoluteness of their manners.  These also would both of them be counteracted by the impossibility of getting further supplies:  for owners, now unable to replace those slaves whom they might lose, by speedy purchases in the markets, would be more careful how they treated them in future, and a better treatment would be productive of better morals.  And here he would just advert to an argument used against those who complained of cruelty in our islands, which was, that it was the interest of masters to treat their slaves with humanity:  but surely it was immediate and present, not future and distant, interest, which was the great spring of action in the affairs of mankind.  Why did we make laws to punish men?  It was their interest to be upright and virtuous:  but there was a present impulse continually breaking in upon their better judgment, and an impulse, which was known to be contrary to their permanent advantage.  It was ridiculous to say that men would be bound by their interest, when gain or ardent passion urged them.  It might as well be asserted that a stone could not be thrown into the air, or a body move from place to place, because the principle of gravitation bound them to the surface of the earth.  If a planter in the West Indies found himself reduced in his profits, he did not usually dispose of any part of his slaves; and his own gratifications were never given up, so long as there was a possibility of making any retrenchment in the allowance of his slaves.—­But to return to the subject which he had left:  He was happy to state, that as all the causes of the decrease which he had stated might be remedied, so, by the progress of light and reformation, these remedies had been gradually coming into practice; and that, as these had increased, the decrease of slaves had in an equal proportion been lessened.  By the gradual adoption of these remedies, he could prove from the report on the table, that the decrease of slaves in Jamaica had lessened to such a degree, that from the year 1774 to the present it was not quite one in a hundred, and that in fact they were at present in a state of increase; for that the births in that island, at this moment, exceeded the deaths by one thousand or eleven hundred per annum.  Barbadoes, Nevis, Antigua, and the Bermudas, were, like Jamaica, lessening their decrease, and holding forth an evident and reasonable expectation of a speedy state of increase by natural population.  But allowing the number of negros even to decrease for a time, there were methods which would ensure the welfare of the West India islands.  The lands there might be cultivated by fewer hands, and this to greater advantage to the proprietors and to this country, by the produce of cinnamon, coffee, and cotton, than by that of sugar.  The produce of the plantations might also be considerably increased,