Medieval spearheads.

Medieval spearhead

Medieval spearheads.

A Phillipine spearhead.

Phillipine spearhead

A Phillipine spearhead.

Prehistoric British spearheads.

Prehistoric British spearheads

Prehistoric British spearheads.

Prehistoric Irish spearheads, made of bronze.

Prehistoric Irish spearheads

Prehistoric Irish spearheads, made of bronze.

3 pointed star

Star

3 pointed star

4 pointed star

Star

4 pointed star

5 pointed star

Star

5 pointed star

6 pointed star

Star

6 pointed star

7 pointed star

Star

7 pointed star

8 pointed star

Star

8 pointed star

9 pointed star

Star

9 pointed star

10 pointed star

Star

10 pointed star

11 pointed star

Star

11 pointed star

12 pointed star

Star

12 pointed star

13 pointed star

Star

13 pointed star

14 pointed star

Star

14 pointed star

15 pointed star

Star

15 pointed star

16 pointed star

Star

16 pointed star

17 pointed star

Star

17 pointed star

18 pointed star

Star

18 pointed star

19 pointed star

Star

19 pointed star

20 pointed star

Star

20 pointed star

21 pointed star

Star

21 pointed star

22 pointed star

Star

22 pointed star

23 pointed star

Star

23 pointed star

24 pointed star

Star

24 pointed star

Illustration of point of tangency (line and circle).

Point of Tangency

Illustration of point of tangency (line and circle).

Illustration of radius drawn to point of contact of a tangent.

Point of Tangency

Illustration of radius drawn to point of contact of a tangent.

"Shows the head of a thyrsus composed of the leaves and berries of the ivy, and surrounded by acanthus leaves. Very frequently, also, a while fillet was tied to the pole just below the head." — Anthon, 1891

Head of a thyrsus

"Shows the head of a thyrsus composed of the leaves and berries of the ivy, and surrounded by acanthus…

Illustration to show if the bisector of the base angles of a triangle are drawn, and through their point of intersection a line is drawn parallel to the base, the length of this parallel between the sides is equal to the sum of the segments of the sides between the parallel and the base.

Triangle With Bisectors of Base Angles

Illustration to show if the bisector of the base angles of a triangle are drawn, and through their point…

Illustration to show the perpendiculars dropped from any point in the equilateral triangle to the three sides is constant, and equal to the altitude.

Perpendiculars Dropped Any Point in the Equilateral Triangle

Illustration to show the perpendiculars dropped from any point in the equilateral triangle to the three…

Illustration to show that the difference of the distances from any point in the base produced of an isosceles triangle to the equal sides of the triangle is constant.

Point in Base of Isosceles Triangle

Illustration to show that the difference of the distances from any point in the base produced of an…

Theory of static equilibrium of mechanism, illustrated b Sir A.B.W. Kennedy.

Wheel Mechanism

Theory of static equilibrium of mechanism, illustrated b Sir A.B.W. Kennedy.

Flat head screw countersunk (set flush) into wood.

Wood Screw Countersunk

Flat head screw countersunk (set flush) into wood.