Tippe Top
A very interesting toy, called the Tippe Top, came into being about 1951. The origin of the toy is uncertain but C.M. Braams of the Physical Laboratory of the Rijks University in Utrecht, Netherlands published an article2 in August-September of 1952 on the theory of its operation. The toy was being sold in Holland at that time. The top has a spherical body with a protruding stem, as pictured. In play one grasps the stem between the index finger and thumb and the top is spun. The top will spin for a short time and then turn over and spin on its stem end. Its motion is totally unexpected when first observed.

The toy became available in England in 1953, being sold by the British Indoors Pastimes Company. One design was given away in cereal boxes in the United States. It can still be purchased at several places in the United States today. The toy was used by one of the writer's physics professors in an Advanced Mechanics class at Michigan State University about 1955.

The commercially available tippe tops are made of molded plastic, with a hollow interior, or else of wood. If one has a drill press with a vise of appropriate design a top can be made from a solid wooden ball. However, it is possible to purchase such wooden balls, or beads, and a top made with minimum equipment. Again, one can find the needed balls at a craft supply store. The writer was able to use a Round "Head" Bead, Item No. 02469, made by the Forster Mfg. Co., Wilton, ME. It is a ball 1-1/4 inches in diameter with a 9/16-inch diameter hole drilled into it to a depth of 1/2-inch. A hole can then be drilled into the center of the countersunk hole for a press-fit insertion of a 1/4-inch diameter dowel, cut so that the distance from the end of the dowel to the bottom of the ball surface is 1-1/2 inches. The top can then be spun relatively slowly and it will be found to invert itself.

The commercially available hollow plastic Tippe Top works very well, in fact, better than the solid wooden ones, and is colored in such a way that its orientation is clear from the color showing while it's spinning. They are usually made with a body diameter of about 1-1/2 inches and a stem length of 1/2-inch.

The tendency of the rotating body to "defy" gravity and rise to a position that seems contrary to expectation and experience can be demonstrated with more familiar objects. If one spins an American football it will tend to rise and spin on its end. One of the smaller size footballs is easier to spin. A smaller object that is capable of exhibiting the same behavior is a hard-boiled egg. In fact, one can distinguish between a hard-boiled egg and one that is not by spinning the egg. An egg that is not hard-boiled will not spin well as it loses energy by the sloshing around that takes place inside the shell. It is said that a school class ring will display the same tendency to rise when spun.

The phenomenon of rising objects that spin was observed over 100 years ago with stones of egg-shape that were found on the beach by Sir William Thomson and Professor Blackburn when the two studied for a mathematical competition at Cambridge University. The Tippe Top was also enjoyed by Wolfgang Pauli and Niels Bohr14.

References
1) C.M. Braams, "The Symmetrical Spherical Top," Nature, Vol 170, Jul 5, 1952, pg 31.
2) C.M. Braams, "On the Influence of Friction on the Motion of a Top," Physica, Vol 18, 1952, pg 503.
3) N.M. Hugenholtz, "On Tops Rising by Friction," Physica, Vol 18, 1952, pg 515.
4) William A. Pliskin, "The Tippe Top (Topsy-Turvy Top)," American Journal of Physics, Vol 22, 1954, pg 28.
5) C.M. Braams, "The Tippe Top," American Journal of Physics, Vol 22, 1954, pg 568.
6) Angelo R. Del Campo, "Tippe Top (Topsy-Turnee Top) Continued," American Journal of Physics, Vol 23, 1955, pg 544.
7) Ira M. Freeman, "The Tippe Top Again," American Journal of Physics, Vol 24, 1956, pg 178.
8) John Perry, Spinning Tops and Gyroscopic Motion, Dover Publications, Inc., New York, 1957, pg 39.
9) John Sattery, "The Breakfast Egg," American Journal of Physics, Vol 26, 1958, pg 341.
10) John B. Hart, "Angular Momentum and Tippe Top," American Journal of Physics, Vol 27, 1959, pg 189.
11) Frank F. Johnson, "The Tippy Top," American Journal of Physics, Vol 28, 1960, pg 406.
12) Gwen White, Antique Toys and Their Backgrounds, Arco Publishing Co., Inc., New York, 1971, pg 45.
13) James C. Lauffenburger, "A Large-Scale Demonstration of the Tippe-Top," American Journal of Physics, Vol 40, 1972, pg 1338.
14) Richard J. Cohen, "The Tippe Top Revisited," American Journal of Physics, Vol 45, 1977, pg 12.
15) Jearl Walker, "The Mysterious 'Rattleback': A Stone That Spins in One Direction and Then Reverses," Scientific American, October 1979, pg 172.
16) Jearl Walker, "The Physics of Spinning Tops, Including Some Far-Out Ones," Scientific American, March 1981, pg 182.