Paper Fiber Impressions on Carbon Tape Ribbons

Abstract

The standard method of identifying a typewriter as having typed a certain document has been to examine the typed impressions on the document for irregularities or identifying characteristics peculiar to that certain typewriter, as distinguished from all other typewriters of the same class. Among the identifying individualities considered are alignment, characters striking off their feet (striking harder on one side of the character than on the other), slant, and damage to the type face. Positive identification requires a sufficient amount of questioned and exemplar type to eliminate the element of chance and establish a definite pattern. In practice, this has not always been easily accomplished. Frequently a very limited amount of typing is available, and additional difficulty arises when the typewriter in question is fairly new and individual identifying characteristics are few.