An illustration showing how to construct an isometric ellipse by compass and six circle arcs. "Divide…

An instrument which could more readily adapt itself to the swaying of the observer's body in a sea-way,…

If a magnetized bar or needle be suspended at its centre of gravity so as to move freely in a horizontal…

"Bring the two ends of the wire into contact, and thus close the circuit. The needle instantly flies…

"A circle may be shaded by shifting the center on a 45-degree line toward the lower right hand corner...…

"A slender length of brass resting in a small brass button and designed to stand vertically on the center…

Still life arrangement including a globe, telescope, book, right angle, rolled map, and dividers.

"Draw a circle three inches in diameter. Divide the circumference into five equal parts by trial with…

"On base AB, 3 1/2" long construct an equilateral triangle, using the 60-degree triangle. Bisect the…

"Draw one and one-half inch square about center of space. Divide AE into four 3/16" spaces, with scale.…