 ### Cause of the Phases of the Moon

During new and full moon, the earth, moon, and sun are all in the same straight line, but, that during… ### Bench Centers

Bench centers are used to check concentrically, parallelism and true rotations of manufactured products. ### Centroid

Illustration showing a centroid, "the curve passing through the successive positions of the instantaneous… ### Invariable Cone

Possible forms of the invariable cone by means of the intersections with a concentric spherical surface. ### Motion of Open Curves

"Since these curves are not closed, one pair cannot be used for continuous motion; but a pair of such… ### Rolling of Equal Ellipses

"If two equal ellipses, each turning about one of its foci, are placed in contact in such a way that… ### Rolling of Equal Hyperbolas

Illustration of the rolling of equal hyperbolas. If two equal hyperbolas are placed so that the distances… ### Rolling of Equal Parabolas

Illustration of the rolling of equal parabolas. "The two parabolas may be considered as two ellipses… ### Gyroscope

"The Gyroscope is an instrument constructed by M. Foucault to make the rotation of the earth visible.… ### Foucault's Gyroscope

"Foucault's Gyroscope. GYROSCOPE. An instrument consisting of a fly-wheel, the axis of which can turn… ### Gyrostat

"Gyrostat. An instrument for illustrating the dynamics of rotation, composed of a box or case having… ### Construction of Logarithmic Spiral

Illustration showing how a rolling logarithmic spiral can be constructed by taking successive values… ### Rolling of Logarithmic Spirals

Illustration showing the rolling of two logarithmic spirals of equal obliquity. ### Lunar Tide

If the earth were uniformly covered with a layer of water, the passage of the moon over any place as… ### Moon Phases

"Let S be the Sun, E the Earth, and A, B, C, D, F, the Moon in different parts of her orbit. Now when… ### Rolling of Non-cylindrical Surfaces

Illustration showing that the rolling of non-cylindrical surfaces. "If the angular velocity ratio of… ### Geometric Block Pattern 1

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 10

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 100

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 101

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 11

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 12

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 13

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 14

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 15

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 16

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 17

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 18

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 19

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 2

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 20

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 21

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 22

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 23

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 24

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 25

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 26

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 27

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 28

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 29

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 3

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 30

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 31

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 32

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 33

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 34

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 35

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 36

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 37

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 38

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 39

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 4

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 40

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 41

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 42

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 43

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 44

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 45

Geometric pattern for translation and rotation exercises. ### Geometric Block Pattern 46

Geometric pattern for translation and rotation exercises.