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Water Reptiles of the Past and Present
by Samuel Wendell WillistonIt was just forty years ago that the writer of these lines, then an assistant of his beloved teacher, the late Professor B. F. Mudge, dug from the chalk rocks of the Great Plains his first specimens of water reptiles, mosasaurs and plesiosaurs. To the youthful collector, whose first glimpse of ancient vertebrate life had been the result of accident..
Illustrations of the Huttonian Theory of the Earth
by John PlayfairA Very little attention to the phenomena of the mineral kingdom, is sufficient to convince us, that the condition of the earth's surface has not been the same at all times that it is at the present moment. When we observe the impressions of plants in the heart of the hardest rocks; when we discover trees converted into flint, and entire beds of lim..
The A.B.-Z. of our own nutrition
by Horace FletcherLuigi Cornaro suggested that all persons in his time ate more than was necessary; most persons ate twice as much as was good for them; and some, who were extravagantly gluttonous, ate ten times as much as was their most economic need; and Cornaro, who was a dissipated wreck at forty, reformed his manner of eating and lived to be a hundred to prove ..
A Preliminary Dissertation on the Mechanisms of the Heavens
by Mary SomervillePhysical astronomy is the science which compares and identifies the laws of motion observed on earth with the motions that take place in the heavens, and which traces, by an uninterrupted chain of deduction from the great principle that governs the universe, the revolutions and rotations of the planets, and the oscillations of the fluids at their s..
Gilbert Weather Bureau (Meteorology) for Boys
by A. C. GilbertIn the minds of most people a very silly notion prevails about the weather and the weather man. They have a general impression that the weather knows no laws—that it is lawless and reckless, fickle and changeable; that the weather man is a sort of conjurer, and by some mysterious gift he is able to prophesy things that most people know nothing abou..
Determination of the Atomic Weight of Cadmium
by Harry C. JonesThe method of weighing the more or less hygroscopic cadmium sulphate is open to criticism when employed in accurate work. The cadmium sulphate was placed in an open boat, dried, cooled over sulphuric acid, and weighed. It was again dried, cooled as before, and weighed. The second weighing could be quickly accomplished since the approximate weight w..
The honey-bee: its nature, homes and products
by William Hetherington HarrisIn these days of intense business-pressure, it is a good thing for men to cultivate hobbies. We say this, notwithstanding the fact that men with hobbies are likely to become bores, from thinking and talking too incessantly of their pet occupations, or are apt to run into extravagant expenditure of time and money, which could be better utilised. Now..
The Foot-prints of the Creator
by Hugh MillerThere are chapters in this little volume which will, I am afraid, be deemed too prolix by the general reader, and which yet the geologist would like less were there any portion of them away. They refer chiefly to organisms not hitherto figured nor described, and must owe their modicum of value to that very minuteness of detail which, by critics of ..