light. The labours of men of genius, however erroneously directed, scarcely ever fail in ultimately turning to the solid advantage of mankind." I listened to his statement, which was delivered without any presumption or affectation; and then added, that his lecture had removed my prejudices against modern chemists; I expressed myself in measured terms, with the modesty and deference due from a youth to his instructor, with- out letting escape (inexperience in life would have made me ashamed) any of the enthusiasm which stimulated my intended labours. I requested his advice concerning the books I ought to procure.
"I am happy," said M. Waldman, "to have gained a disciple; and if your application equals your ability, I have no doubt of your success. Chemistry is that branch of natural philosophy in which the greatest improvements have been and may be made: it is on that account that I have made it my peculiar study; but at the same time I have not neglected the other branches of science. A man would make but a very sorry chemist if he attended to that department of human knowledge alone. If your wish is to become really a man of science, and not merely a petty experimentalist, I should advise you to apply to every branch of natural philosophy, including mathematics."
He then took me into his laboratory, and explained to me the uses of his various machines; instructing me as to what I ought to procure, and promising me the use of his own when I should have advanced far enough in the science not to derange their mechanism. He also gave me the list of books which I had requested; and I took my leave.
Thus ended a day memorable to me: it decided my future destiny.
FROM this day natural philosophy, and particularly chemistry, in the most comprehensive sense of the term, became nearly my sole occupation. I read with ardour those works, so full of genius and discrimination, which modern inquirers have written on these subjects. I attended the lectures, and cultivated the