The investigation of the laws by which the general mortality of the human species appears to be governed is of equal importance to the statesman, the physician, the natural philosopher, and the mathematician; and as you have had occasion to pay particular attention to the subject, I trust that it will not be disagreeable to you to receive the results of an inquiry, into which I have entered, for the purpose of appreciating, if not of reconciling, the many discordant opinions that have been advanced respecting the comparative mortality of mankind, at different times and under different circumstances.