Alchemy, a pseudo chemistry, the precursor, in the middle ages, of the modern science, had for its primary object the transmutation of metals into gold and silver by the discovery of a universal solvent containing the primary principle of all matter. This solvent, called the philosophers stone, was supposed to possess the power of renewing life and eliminating disease. Harmes Trismegistus, an ancient Egyptian king, was claimed to be the founder of alchemy by the alchemists. Among its devotees were Roger Bacon, Albertus Magnus, Valentinus, Paracelsus, and others.

Nocturnal creatures are generally supposed not to see well in the daylight, but facts collected are gradually dispelling the idea. It is well known that felines, which see well by night, seem to be able to see quite as well by day, and this is being found true of many other creatures. The bat sees admirably by daytime, as anyone can ascertain by threatening it with a twig. The owl also has first-rate day sight. Night-flying lepidoptera, when disturbed in their places of refuge during the day, have no difficulty in seeing at once where is the nearest and best place for a temporary refuge.

When animals or plants are removed from their peculiar and natural districts to one entirely different in climate some surprising changes take place. As soon as possible after such removal they change their character and habits so as to conform with their new homes, or else cease to exist. A good wool-bearing sheep transferred from some northern pasture to the tropics changes his coat to a thin covering of straggling hairs scarcely resembling wool; the dog becomes destitute of hair altogether, and even bees cease to lay up their stores of honey, and in a great measure lose their industrious habits.

We apply the term buoyancy to that quality whereby a ship, or any other floating body, is enabled to support a certain weight. In the case of a ship, it is necessary that such weight should be carried without her sinking too deeply in the water, or floating too lightly on it. The weight of a ship not loaded with any cargo, is exactly equivalent to the weight of the volume of water she displaces. Therefore, given a certain draught-line to which a ship is to be loaded, multiply the number of cubic feet of the volume of the immersed part by the weight of a cubic foot of sea-water (64 lb.), and the product will be the weight of water displaced by the ship at the given draught-line. If from this the weight of a ship herself be subtracted, the residue is the amount of extra weight, or cargo she is capable of carrying at that draught-line, and is a measure of her quality of buoyancy.

Vivisection is a term applied to experiments upon animals for the purpose of physiological and pathological investigation. The term, although strictly applicable only to cutting operations is extended so as to embrace all scientific operations upon living animals, such as the administration of poisons and the innoculation of disease. The anti-vivisection movement commenced in 1859 with the societies for the prevention of cruelty to animals in Dresden and Paris. By the act of 1876, regulating vivisection, vivisectors must have a license or certificate, the experiment must be performed in a registered place, and the animal to be experimented upon must be rendered insensible by an anaesthetic. In Great Britain, in 1880, there were thirty-three persons licensed to vivisect and three hundred and eleven experiments; in 1889 the numbers had risen to eighty-seven and 1,417.

A planet is said to be in conjunction with another body when it has the same longitude, and is seen in the same direction in the heavens. It is obvious that in the case of the inferior planets this conjunction will be of two kinds: the one when the planet is between the Earth and the Sun, called inferior conjunction; and the other when at the opposite point of of its orbit, with the Sun between the planet and the Earth, called superior conjunction. The latter is the only kind of conjunction that can happen to the superior planets Mars, Jupiter, Saturn, Uranus and Neptune; the inferior planets, Mercury and Venus, being subject to both positions.

In many mountain ranges rent by the action of torrents, isolated cliffs have been left standing like monuments of former geological periods while the softer strata of gravel and loose rocks have been washed away, with the exception perhaps of a massive boulder resting, as it were, upon the roof of a tower-like crag. On the island of Mauritius that arrangement repeats itself on a marvelous scale in the mountain peak known as "Peter Botte" a monolith towering above the coast range to a height of more than 2,000 feet and supporting a rock so much broader than its pedestal that it gives the combination the appearance of an inverted pyramid or a gigantic toad-stool.

The stars which stud the firmament have, from a time earlier than authentic records can trace, been formed into artificial groups, which have received names borrowed from fancy or fable, mainly from Greek mythology. These groups are called constellations. Though quite devoid of anything like systematic arrangement, this traditional grouping is found a sufficiently convenient classification, and still remains the basis of nomenclature for the stars among astronomers. They are divided into northern, southern and zodiacal constellations. In old authors, "constellation" is used to signify the relative positions of the planets at a given moment.

It is only within a few years, one might almost say months, that the wide effect of the warm, moist Pacific winds, called chinooks, has been known in British Columbia and Alaska. These winds, corresponding exactly to those that make England a fertile country in the latitude of Labrador, keep the snow melted from the plains at the eastern base of the Rockies, and they encourage a magnificent growth of root crops, cabbage, oats and grass a thousand miles north of New York. Wheat does not do well and berries are small, though little attempt has been made to cultivate fruit. The winters are biting cold, but dry, and the summer, though short, is so hot that vegetation comes out of the earth with a rush.