INDEX,

Copernican or Pythagorean System, iii. 97. Why socalled, iii. 103 n. By wsiom adopted, ibid.

Cornea , see Eye.

Crane , see Syphon.

Crepusculum, where least, and where greatest, iii.184 n.

Crystalline Humour, see Eye.

Cupping accounted for by the Spring of the Air, ii.177.

Curve , hyperbolic, formed by Water in Glass Planesdemonstrated, i. 25 n. Surfaces, the Descent ofBodies on, i. III. Sec Motion.

Cycle of the Sun, to find any Year of, exemplified bya Table, iii. 243, its seq. Metonic, what, iii. 244.Explained, ibid. & seq. Of Induction what, iii.246. How many, iii. 241. Of the Sun accountedfor, ibid.

Cycloid, Nature and Use of in Pendulums and Time-keeping Instruments, i. 118 n. Nature cf illu-strated, i. its seq. Several Particulars relating toa Pendulum, i. 121 n. Property of, i. 127. TheCurve of quickest Descent demonstrated, i. 128 n.its seq.

D

r\ AT, natural, what, iii. 223. Solar, what, iii. 231.■M' Sidereal, what, ibid. Illustrated an! explained, iii.its seq. Begins differently in different Parts of theWorld, iii. 236.

Declination and Inclination of the Needle what, i. 46 n.

Of the Sun and Stars, what, iii. 256.

Density, what, i. 84 n. Proportions of, what, ibid.Of the Air different and why, ii. 136. How it de-creases upwards, ii. 137.

Derham, Dr. measured the Velocity of the Wind,ii. 2/1 n. Table of Experiments made on Gunsat 12 Miles distant, ii, 244 n.

Desaguliers , Dr. his Improvements to the Fire Engine forraising Water by Steam, exhibited and explained, ii.87 n.

Descent of Fluids by what caused, ii. 2 . Of Bodies by'Gravity in what Direction, i, 83. See Bodies'.

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