US296018A - Educational - Google Patents

Description

(No Model.)

* A. H. KENNEDY.

EDUCATIONAL APPLIANCE.

No. 296,018. Patented Apr. 1, 1884'.

N PETERS. Phmo-lilhumpher, Wahinflbn. I7. (I.

UNITED STATES PATENT" OFFICE.

ALBERT H. KENNEDY, OFROCKPORT, INDIANA.

EDUCATIONAL APPLIANCE.

SPECIFICATION forming part of Letters Patent No. 296,018, dated April 1, 18 84. Application filed October 29, 1883. (No model.)

To all whom it may concern.-

Be it known that I, A. H. KENNEDY, of Rockport, in the county of Spencer and State of Indiana, have invented certain new and useful Improvements inEd ucational Appliances; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use it, reference being had to the accompanying drawings, which form part of this specification.

My invention relates to an improvement in educational appliances; and it consists in'the combination ofa cylinder, a cone, and a semispherical cup, all of the same diameters, the cylinder and the cone being secured together, as will be more fully described hereinafter.

The object of my invention is to demonstrate by experiment several geometrical truths, and is to be used in teaching geometry.

Figure 1 represents a perspective of the cone and the cylinder. Fig. 2. is a separate view of the hemisphere.

A represents the cylinder, which will have a length just equal to its diameter. Inside of this cylinder is secured a cone, 0, which has the same diameter as the cylinder, and which is of the same length. as the'cylinder. In connection with these two bodies I use a semisphere, D, which has the same diameter as the cone and the cylinder.

Instead of the cone being secured in the cylinder, as here shown, the semi-sphere may be secured to it in the same manner. All three of these bodies will be made of tin, brass, or some other cheap material. Two of the parts are connected together for convenience of demonstration.

The three bodies demonstrate the following: First, the convex surface of the cylinder is equal to the surface of a sphere of the same diameter; second, the semi-sphere emptied in a cone of the. same diameter, and having a length equal to its diameter, will exactly fill it; third, a semi-sphere emptied twice into a cylinder of the same diameter, and having the same length at its diameter, and around a cone, which has the same diameter and length as the cylinder, fills the space between the cylinder and the cone exactly. These experiments show that a cone is equivalent to one-third of the circumscribed cylinder of the same diameter and length, and that a globe is two-thirds of the circumscribed cylinder of the same diame ter, and having a length equal to its diameter. The cone and cylinder being secured together, the semi-sphere is used to fill them. Should the semisphere be secured to the cylinder, the cone will then be used to fill the other two.

Having thus described my invention, I claim An illustrative apparatus for showing the volume of symmetrical solids, consisting of a hollow cylinder and cone of the same diameter and height, the cone being secured inside of the cylinder, and a hollow hemisphere of the same diameter as the other parts, all adapted to be used together,for the purpose described.

In testimony whereof I affix my signature in presence of two witnesses.

ALBERT H. KENNEDY.-

Witnesses:

FRANCIS .I. REINHARD, W. T. MASON.

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