"This is a game of pure manual dexterity, and is rare practice for cultivating steadiness of hand and delicacy of touch. Its worst fault is that in the very nature of the game a constant series of deadlocks are inevitable, only to be overcome by the self-sacrifice of one or other of the players. Jackstraws are a number of thing narrow slips of wood, bone or ivory, each more or less notched, sometimes cut into fantastic shapes, and numbered. These being held together in a bundle, are allowed to fall on the table, and the players, two or more in number, each in turn pull them out one by one with a small hook. As long as a player can go on abstracting from the heap, without in any way shaking or disturbing more than one jackstraw at the time, his turn continues, and all he thus secures he keeps; at the least shake his turn ceases, and the next player goes on. When all the jackstraws have been thus abstracted, each player counts his heap, each jackstraw being valued at the number inscribed on it, and he who has most wins."— Thomas Sheppard Meek

Jackstraws

"This is a game of pure manual dexterity, and is rare practice for cultivating steadiness of hand and…

A rectangle is a parallelogram whose angles are all right angles.

Rectangle

A rectangle is a parallelogram whose angles are all right angles.

A square is a rectangle whose sides are all of the same length.

Square

A square is a rectangle whose sides are all of the same length.

A rhomboid is a parallelogam whose opposite sides are equal, and whose angles are not right angles.

Rhomboid

A rhomboid is a parallelogam whose opposite sides are equal, and whose angles are not right angles.

A rhombus is a rhomboid having equal sides.

Rhombus

A rhombus is a rhomboid having equal sides.

A trapezoid is a quadrilateral having only two of its sides parallel.

Trapezoid

A trapezoid is a quadrilateral having only two of its sides parallel.

An isosceles triangle is one having two of its sides equal.

Isosceles

An isosceles triangle is one having two of its sides equal.

An equilateral triangle is one having all of its sides equal.

Equilateral

An equilateral triangle is one having all of its sides equal.

A scalene triangle is one having no two of its sides equal.

Scalene

A scalene triangle is one having no two of its sides equal.

A right-angled triangle is any triangle having one right angle. The side opposite the right angle is called the hypotenuse. A right-angled riangle may be isosceles or scalene.

Right-Angled

A right-angled triangle is any triangle having one right angle. The side opposite the right angle is…

A machine used to press metal in to different shapes.

Stamping Machine

A machine used to press metal in to different shapes.

"Suppose a number of vessels, of different shapes and sizes to have a communication between them, by means of a small tube, passing from the one to the other. If, now, one of these vessels be filled with water, or if water be poured into the tube A, all the other vessels will be filled at the same instant, up to the line B C. Therefore, the pressure of the water A, balances that in 1, 2, 3, while the pressure in each of these vessels is equal to that in the other, and so an equilibrium is produced throughout the whole series." —Comstock, 1850

Water Pressure

"Suppose a number of vessels, of different shapes and sizes to have a communication between them, by…

"The elliptical circle being supposed to be the Earth's orbit, with the Sun, S, in one of the foci. Now the spaces, 1, 2, 3, etc., though of different shapes, are of the same dimensions, or contain the same quantity of surface. The Earth, we have already seen, in its journey round the Sun, describes an ellipse, and moves more rapidly in one part of its orbit than in another. But whatever may be its actual velocity, its comparative motion is through equal areas in equal times. Thus its center passes from E to C, and from C to A, in the same period of time, and so of all the other divisions marked in the figure." —Comstock, 1850

Elliptical Orbit

"The elliptical circle being supposed to be the Earth's orbit, with the Sun, S, in one of the foci.…

A cube

Cube

A cube

A 1/2 cube

Half Cube

A 1/2 cube

An 1/8 cube.

Eighth Cube

An 1/8 cube.

An 1/4 cube

Fourth Cube

An 1/4 cube

A gable

Gable

A gable

A 1/2 gable

Half Gable

A 1/2 gable

A pyramid

Pyramid

A pyramid

An arch

Arch

An arch

A cylinder

Cylinder

A cylinder

This doodad has floral and vinelike shapes inside a square shape.

Doodad

This doodad has floral and vinelike shapes inside a square shape.

Its calyx and corolla displayed; the five large parts are the sepals; the four smaller, of two shapes, are the petals; the place of the fifth petal is vacant.

Larkspur

Its calyx and corolla displayed; the five large parts are the sepals; the four smaller, of two shapes,…

Glandular epithelium with the cells set round a simple saccular gland, highly magnified. "Glandular epithelium is found in the recesses of secreting glands. The cells are of many different shapes, and are usually set round a tubular or saccular cavity, into which the secretion is poured." —Kimber, 1907

Glandular Epithelium Cells

Glandular epithelium with the cells set round a simple saccular gland, highly magnified. "Glandular…

Forms of cells from the body, showing their various shapes.

Forms of Cells

Forms of cells from the body, showing their various shapes.

Illustration of odd shape with squares drawn to demonstrate area.

Area of Odd Shapes

Illustration of odd shape with squares drawn to demonstrate area.

Cross section of road that can be used to find area of composite figures.

Cross Section of Road

Cross section of road that can be used to find area of composite figures.

Cross section of steel beam that can be used to find area of composite figures.

Cross Section of Beam

Cross section of steel beam that can be used to find area of composite figures.

A grid with the corners of each square marked by cross shapes.

Cross Grid

A grid with the corners of each square marked by cross shapes.

A grid with the corners of each square marked by cross shapes.

Cross Grid

A grid with the corners of each square marked by cross shapes.

Illustration of a semicircle.

Semicircle

Illustration of a semicircle.

Illustration of a sphere generated by the revolution of a semicircle ACB about its diameter AB as an axis.

Sphere Made by Revolution of Semicircle

Illustration of a sphere generated by the revolution of a semicircle ACB about its diameter AB as an…

Illustration of a plane passing through a sphere.

Plane Passing Through a Sphere

Illustration of a plane passing through a sphere.

"Every section of a sphere made by a plane is a circle."

Circle Made by Plane Passing Through a Sphere

"Every section of a sphere made by a plane is a circle."

A sphere with arcs drawn.

Sphere With Arcs

A sphere with arcs drawn.

A sphere with arcs and poles. "The distance of all points in the circumference of a circle of a sphere from its poles are equal."

Sphere With Arcs and Poles

A sphere with arcs and poles. "The distance of all points in the circumference of a circle of a sphere…

A sphere with quadrants drawn on it.

Sphere With Quadrants

A sphere with quadrants drawn on it.

A sphere with quadrants and poles. "A point on the surface of a sphere, which is at the distance of a quadrant from each of two other points, not the extremities of a diameter, is a pole of the great circle passing through theses points."

Sphere With Quadrants and Poles

A sphere with quadrants and poles. "A point on the surface of a sphere, which is at the distance of…

Illustration of a material sphere that can be used to find its diameter.

Material Sphere

Illustration of a material sphere that can be used to find its diameter.

Illustration of a sphere with a tangent plane. "A plane perpendicular to a radius at its extremity is tangent to the sphere."

Sphere With Tangent Plane

Illustration of a sphere with a tangent plane. "A plane perpendicular to a radius at its extremity is…

Illustration of a sphere with a tangent plane. "A plane perpendicular to a radius at its extremity is tangent to the sphere."

Sphere With Tangent Plane

Illustration of a sphere with a tangent plane. "A plane perpendicular to a radius at its extremity is…

Illustration of a sphere inscribed in a tetrahedron.

Sphere Inscribed in Tetrahedron

Illustration of a sphere inscribed in a tetrahedron.

Illustration of a sphere inscribed in a tetrahedron.

Sphere Inscribed in Tetrahedron

Illustration of a sphere inscribed in a tetrahedron.

Illustration of two intersecting spheres. "The intersection of two spherical surfaces is the circumference of a circle whose plane is perpendicular to the line joining the centres of the surfaces and whose centre is in that line."

Intersecting Spheres

Illustration of two intersecting spheres. "The intersection of two spherical surfaces is the circumference…

Illustration of a sphere with arcs drawn.

Arcs Drawn on Sphere

Illustration of a sphere with arcs drawn.

Illustration of a sphere with a polyhedral angle whose vertex is at the center of the sphere and whose face angles are measured by the sides of the polygon, whose dihedral angles have the same numerical measure as the angles of the polygon.

Polyhedral Angle in a Sphere

Illustration of a sphere with a polyhedral angle whose vertex is at the center of the sphere and whose…

Illustration of a sphere with a polyhedral angle.

Polyhedral Angle in a Sphere

Illustration of a sphere with a polyhedral angle.

Illustration of polar and spherical triangles.

Polar and Spherical Triangles

Illustration of polar and spherical triangles.

Illustration of polar triangles.

Polar Triangles in Sphere

Illustration of polar triangles.

Illustration of symmetrical spherical triangles.

Symmetric Spherical Triangles

Illustration of symmetrical spherical triangles.

Illustration of symmetrical spherical triangles.

Symmetric Spherical Triangles

Illustration of symmetrical spherical triangles.

Illustration of symmetrical spherical triangles.

Symmetric Spherical Triangles

Illustration of symmetrical spherical triangles.

Illustration of equal spheres with equal triangles.

Equal Spheres With Triangles

Illustration of equal spheres with equal triangles.

Illustration of equal spheres with equilateral and equiangular triangles.

Equal Spheres With Triangles

Illustration of equal spheres with equilateral and equiangular triangles.

Illustration of an isosceles spherical triangle.

Isosceles Spherical Triangle

Illustration of an isosceles spherical triangle.

Illustration of an isosceles spherical triangle.

Isosceles Spherical Triangle

Illustration of an isosceles spherical triangle.

Illustration of an isosceles spherical triangle.

Solids of Revolution

Illustration of an isosceles spherical triangle.

Illustration of a semicircle with chords and radii.

Semicircle With Chords and Radii

Illustration of a semicircle with chords and radii.