Ax questions, hard answers
Another hypothesis for the polish on the Stone Age corundum ax head is that the Stone Age people never had absolutely pure corundum, which indeed would have required diamond to polish ("In the Buff: Stone Age tools may have derived luster from diamond," SN: 2/19/05, p. 116). It is possible that these people used one grade of corundum to make the ax head and a slightly harder grade to polish it. The difference in hardness would serve the purpose.
James E. Burkart
Researcher Peter J. Lu says that his group tried pure corundum, the highest-grade possible, as well as quartz and diamond, to polish the ax. Only the diamond produced the smoothness of the original axe heads.—A. Goho
The article was very interesting. In looking at the photo, however, the first question that came to my mind was, How did these Stone Age craftsmen create the large round hole through the ax?
Early in our history, U.S. citizens ate bushmeat ("Bushmeat on the Menu," SN: 2/26/05, p. 138). We hunted deer, bear, squirrel, rabbit, possum, turkey, pheasant, armadillo, and other wild game. We hunted because it was easier to hunt than to earn the money necessary to buy meat. We diminished our supply of wild game. Africans are simply doing what we used to do. As populations grow and prosper there, I predict they will increasingly rely on the more easily accessible supply of ranch-raised meat.
Joye R. Swain
Oklahoma City, Okla.
It's in the blood
"Healing secret lies in blood" (SN: 3/5/05, p. 157) appears to suggest that healing of old people could be promoted by young people's blood. Perhaps there is something to the Dracula story after all. Young people give blood for money. Anything known about the effect of transfusions on old people?
The mice in this experiment exchanged far more blood than the comparable volume in most transfusions, which the researchers say probably wouldn't be enough to exert the healing effect. They add that they know of no one keeping track of the ages of blood donors and recipients.—C. Brownlee