It therefore happened that this venial fault of my uncle's came to be pretty well understood in time, and an unfair advantage was taken of it; the students laid wait for him in dangerous places, and when he began to stumble, loud was the laughter, which is not in good taste, not even in Germans. And if there was always a full audience to honour the Liedenbrock courses, I should be sorry to conjecture how many came to make merry at my uncle's expense. Nevertheless my good uncle was a man of deep learning--a fact I am most anxious to assert and reassert. Sometimes he might irretrievably injure a specimen by his too great ardour in handling it; but still he united the genius of a true geologist with the keen eye of the mineralogist. Armed with his hammer, his steel pointer, his magnetic needles, his blowpipe, and his bottle of nitric acid, he was a powerful man of science. He would refer any mineral to its proper place among the six hundred [1] elementary substances now enumerated, by its fracture, its appearance, its hardness, its fusibility, its sonorousness, its smell, and its taste. The name of Liedenbrock was honourably mentioned in colleges and learned societies. Humphry Davy, [2] Humboldt, Captain Sir John Franklin, General Sabine, never failed to call upon him on their way through Hamburg. Becquerel, Ebelman, Brewster, Dumas, Milne-Edwards, Saint-Claire-Deville frequently consulted him upon the most difficult problems in chemistry, a science which was indebted to him for considerable discoveries, for in 1853 there had appeared at Leipzig an imposing folio by Otto Liedenbrock, entitled, "A Treatise upon Transcendental Chemistry," with plates; a work, however, which failed to cover its expenses. To all these titles to honour let me add that my uncle was the curator of the museum of mineralogy formed by M. Struve, the Russian ambassador; a most valuable collection, the fame of which is European. Such was the gentleman who addressed me in that impetuous manner. Fancy a tall, spare man, of an iron constitution, and with a fair complexion which took off a good ten years from the fifty he must own to. His restless eyes were in incessant motion behind his full-sized spectacles. His long, thin nose was like a knife blade. Boys have been heard to remark that that organ was magnetised and attracted iron filings. But this was merely a mischievous report; it had no attraction except for snuff, which it seemed to draw to itself in great quantities. When I have added, to complete my portrait, that my uncle walked by mathematical strides of a yard and a half, and that in walking he kept his fists firmly closed, a sure sign of an irritable temperament, I think I shall have said enough to disenchant any one who should by mistake have coveted much of his company.