If perfection of climate is sought, perfect sanitation obtained, regularity, cleanliness, uprightness, temperance, and self-control practiced, if the bodily waste is supplied with nature's fruits, grains, vegetables, and herbs, if drinking is done at nature's fountain for thirst, life will be prolonged to see the light in more than one century. Finally, add to that, if self is forgotten, and only the comfort of others remembered and regarded, life may be indefinitely prolonged. M. Chevreul, the eminent French scientist, died April 9, 1889, aged 103 years. "On the 31st day of August, 1886, he attained the age of 100 years, and was still in vigorous health, and with all his faculties unimpaired. The occasion 'was celebrated by the students of Paris, among whom he is a great favorite, and by the French people generally, with enthusiasm.' The Paris _Journal Illustre_ seized upon the opportunity to interview him in a manner that is described as marking 'an era in this line of journalistic enterprise. Not only were his words taken down _verbatim_, but his various attitudes while speaking were photographed by the instantaneous process, and engraved,' twelve illustrations being given in the interview. M. Chevreul is an important figure in the scientific world, and the interview contains many useful lessons in hygiene and philosophy, not the least of which is described by his interviewer as an exposition of the 'chemical secret of longevity.' In a condensed form, it is as follows: He regards longevity as a great blessing, and declares that the method by which it may be secured is easy to learn; but I think that with many people it would be difficult to follow. He laid down the proposition that the larger proportion of the human race die of disease and not of old age. Now, he finds that while we should especially guard against drawing general conclusions from particular cases, yet it is nevertheless true that the study of particular cases may and should conduct us to general precepts. It is necessary for each one to study his personal aptitudes, and conform to them with a constant firmness. Every _r'egim'e_ is personal, and 'I cannot too much insist upon this essential point, that what is suitable for one may not be for another. It is, then, important for each one to note well what is adapted to his own constitution. Thus, I have the same aversion to fish as to fermented liquors, especially to wine, also a distaste for a large number of vegetables, and I could never drink milk. Shall I conclude, then, that fish, that the vegetables which I do not relish, and milk, are not nutritive?--Certainly not; for I judge by a general rule and not by my own idiosyncrasies. Coffee and chocolate agree with me; the latter is especially nutritive, and gives me an appetite for food. It is for me an aperient. Shall I conclude from this that chocolate would give everybody an appetite?'