“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 acquaintance of the men of science of the university, and I found even in M. Krempe a great deal of sound sense and real information, combined, it is true, with a repulsive physiognomy and manners, but not on that account the less valuable. In M. Waldman I found a true friend. His gentleness was never tinged by dogmatism, and his instructions were given with an air of frankness and good nature that banished every idea of pedantry. In a thousand ways he smoothed for me the path of knowledge and made the most abstruse inquiries clear and facile to my apprehension. My application was at first fluctuating and uncertain; it gained strength as I proceeded and soon became so ardent and eager that the stars often disappeared in the light of morning whilst I was yet engaged in my laboratory.