Synopsis of Universal Geometry (1644) - Page 30

Homologous magnitudes original: "Homologæ magnitudines". These are corresponding parts in similar geometric figures. 14
What the horizon is 249
The astronomical and sensible horizon 265. its size.
Functions of the horizon 266
The horopter, where it is The horopter is the line or surface in the field of view where objects are perceived as single during binocular vision. 492
The plane of the horopter 490
The difficulty of the shoulder in carrying loads 455
Properties of liquids 144
The foci of hyperbolas and ellipses original: "vmbilici", literally navels. In geometry, these are the focal points of a conic section. 335
Comparison of the hyperbola with other lines 432
Generation of the hyperbola 281. its definition 334
Hyperbolic and parabolic spindles A spindle is a solid of revolution generated by a curve rotating around a chord. 173
Comparison of the hyperbolic conoid with other bodies 432 & 433
An infinite hyperbolic solid equal to a finite cylinder, in the preface at point V. This refers to the paradox of Torricelli's Trumpet, a shape with an infinite surface area but a finite volume.
Hypotheses of Archimedes 93
Physical hypotheses of light and vision 567

I

Ichnography, what it is Ichnography refers to the drawing of a ground plan or a map. 543
Icosahedron A regular solid with twenty triangular faces. 88. & 43
Icosidodecahedron 59. its comparison with the cube and other bodies 61
Fire transmitted through light This likely refers to the use of burning mirrors to concentrate sunlight. 510
Location of an image 501
Vision of an image, its location 475
Location of an image in mirrors, where it is 503
Property of an upright image through a convex lens 523
A refracted image and its location 515
An image in a rarer or denser medium 516
Diameter and center of incidence 550
Line of incidence, point of incidence 500. the perpendicular and the angle 501
Inclination of a conoid floating in liquid, when it occurs 152
Inclination of a surface upon a surface 190.
What inclination is 190. and its angle in the same place.

Restored inclinations original: "Inclinationes restitutæ". This refers to a lost work by Apollonius of Perga concerning geometric constructions. 388
The index and the crossbar Parts of a surveying or astronomical instrument. 71
Four infinites 457
An infinite plane space equal to a finite one, in the preface at point V.
Inscribed lines 77
Reciprocals of inscribed regular bodies 53
An instrument for capturing the size of the sun 156
The same instrument used for catoptrics and dioptrics Catoptrics is the study of mirrors. Dioptrics is the study of the refraction of light through lenses. 518
Irrational magnitudes 30
The iris of cats Likely discussing the optical properties of a cat's eye. 487
Isosceles A triangle with two equal sides. 2
Which of the isoperimetric shapes is the largest Isoperimetric shapes share the same perimeter. The circle contains the largest area among them. 369

L

What kind of man Lacombe is in Theology, in the preface at point XIV. Probably a reference to a contemporary scholar or critic.
The Laconian scytale The scytale was an ancient Greek tool used for cryptography, involving a strip of parchment wrapped around a rod. 467
The sides of a pyramid, cube, and icosahedron compared 55
Which are the circles of latitude 253
From where celestial latitude is taken, in the same place.
Latitude on the meridian 264. & 265
A lemma having 18 modes 24
How concave and convex lenses concur for vision, from 510 to 524.
Effects of a concave and convex lens 527 and following.
Properties of convex lenses in representing objects 523
The French league, consisting of 2500 fathoms original: "sexpedarum", meaning six-foot measures. 259
Description of levity In early physics, levity was considered a positive force of lightness, the opposite of gravity. 396
The center of levity 197
Frauds involving balances original: "Librarum". Here refers to weighing scales. 448
Three types of balances, and which is better 449
Arms of a balance proportional to weights 439
Why larger balances are more exact 448
Various balances and their laws 441
How the center of a balance is to be found in the same place