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Water Reptiles of the Past and Present

Water Reptiles of the Past and Present

by Samuel Wendell Williston

It 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

Illustrations of the Huttonian Theory of the Earth

by John Playfair

A 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

The A.B.-Z. of our own nutrition

by Horace Fletcher

Luigi 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

A Preliminary Dissertation on the Mechanisms of the Heavens

by Mary Somerville

Physical 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

Gilbert Weather Bureau (Meteorology) for Boys

by A. C. Gilbert

In 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

Determination of the Atomic Weight of Cadmium

by Harry C. Jones

The 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

The honey-bee: its nature, homes and products

by William Hetherington Harris

In 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

The Foot-prints of the Creator

by Hugh Miller

There 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 ..