Browsing named entities in Knight's Mechanical Encyclopedia (ed. Knight). You can also browse the collection for 1684 AD or search for 1684 AD in all documents.

Your search returned 7 results in 3 document sections:

Knight's Mechanical Encyclopedia (ed. Knight), A. (search)
was used by Dr. Papin of France about 1695, but had been described nearly two thousand years previously by Hero in his Spiritalia. It was attached by Perrault, in 1684, to the fire-engine (Pompe Portative) of Duperrier. Air-chamber. It is intended to equalize the flow of water from a reciprocating pump. The action of the pu composed of two graduated circles, one vertiealand the other horizontal. It is thus of general application. Jean Pieard, the great French astronomer, 1620 – 1684, is said to have been the first to apply the telescope in the measurements of angles. Al-tom′eter. A name for the theodolite, which see. Al′to-rili-evo. agnitude and importance, and the most stupendous work of the kind ever projected originated in France. This was the aqueduct of Maintenon, which was undertaken in 1684 and abandoned in 1688, during which time 22,000,000 francs are said to have been expended upon it. It was intended to have brought water from the river Eure at Pon<
Knight's Mechanical Encyclopedia (ed. Knight), M. (search)
diaphragm in his telescope, crossing each other at right angles and dividing the field of view into squares of equal size. Azout, a French astronomer, published an account of the micrometer in 1667. Picard, another French savant, who died in 1684, was instrumental in the practical application of the micrometer to instruments. He early adapted the telescope to the measurement of angles, and determined with reasonable correctness the length of a degree, which he measured by means of an odomessful attempt was made in France as early as 1634 to establish glass-houses for manufacturing mirrors, and in 1665 Nicholas de Mayer obtained a patent from the French government, and proceeded to erect works for the purpose. This patent was in 1684 renewed for thirty years, but in 1688 Abraham Thevart succeeded in casting at Paris plates of a size which astonished all who saw them; they were 84 inches long and 50 broad, while the largest of those previously made had not exceeded 45 or 50 inc
Knight's Mechanical Encyclopedia (ed. Knight), T. (search)
of the handles, and their occasional entire disappearance. But the merit of having explained scientifically all the phenomena of the ring of Saturn taken as one belongs to Huyghens (1655). Dominic Cassini first saw the black stripes in the ring (1684), and recognized its division into at least two concentric rings. The spots on the sun were first observed through telescopes by John Fabricius of East Friesland, and by Galileo either at Padua or Venice. Fabricius published his discovery in Jry planets, did not seek to discover any more of them. Four other of Saturn's moons were discovered by Dominic Cassini; the seventh, or outermost, which has great alternations of brightness, in 1671, the fifth in 1672, and the third and fourth in 1684, with an object-glass of Campani's having a focal length of 100-136 feet. The two innermost, or the first and second, were discovered in 1788 and 1789 by Herschel, with his colossal reflector. The second satellite offers the remarkable phenomenon