Once we have separated the animal hairs from the human hairs, our next problem is determining the race of the individual from whom the particular human hairs in which we are interested originated.
Looking at the hair under low power—under a low-power microscope—we find that a Caucasian hair differs from the hair of the Negroid or Mongoloid race in diameter fluctuation. The hair shaft varies in width through its entire length. I might take, for instance, this yellow or this black pencil. Here we find that the diameter of the pencil is uniform through the entire length. Now, if we would twist this pencil we would change the diameter of the pencil slightly. This would be so in a Caucasian hair, where there might be slight fluctuations in a hair, such as a person with wavy hair would have a slight fluctuation. The person with straight hair has hair shafts which for all practical purposes, are uniform in diameter the entire length.
In Negroid hair, there is great fluctuation. Their hair is very curly and kinky. This is caused by the great fluctuation present in their hairs.
Mr. Eisenberg. You mean in the diameters?
Mr. Stombaugh. Yes; diameters.
In Mongoloid hair, which includes Asiatic and North American Indians, there is little or no fluctuation present in their hairs.
Going back to the Caucasian hair, the color of the Caucasian individual's hair differs from black to blond and, of course, white.
Negroid hairs are dense black usually; some are white. There are a few exceptions here where we find some redheaded persons of this race. The Mongoloids are always black, but not quite as dense black as those of the Negroid race.
The texture of the hair: Caucasian head hairs, are very soft, flexible; Negroid hairs are very stiff and wiry; and Mongoloid hairs are flexible, but not as soft and flexible as the Caucasian.
Now, as to the general width, or rather diameter, of the shaft, we find Caucasian is medium, the Negroid is medium, the Mongoloid hairs are much larger than either the Negroid or the Caucasian.