Pages are typewritten with some handwritten corrections to the text. Some photographs of wiring of the machinery; drawings of emitter, etc; 1 illustration apparently colored-in much later with colored pencil. Text printed on single-sided pages.

INCLUDES -- Illustration of Machine (labelled Hollerith) (includes photo of wiring); Build;

THEORY AND OPERATION -- Introduction; Rolling Total Functions; Rolling Total Mechanisms; Counter Operation; Emitter Operation; Theory of Performance -- Minor, Inter, and Major Control; Subtraction; Cross Addition; Cross Addition and Subtraction; Cycles; Operation of Elusive 1; Distribution Methods; Group Speeds; Alphabet; Statement Device and Entry Control Operation.

'Feature -- Counters and Print Banks in flexible connection - any Counter to any like Print Bank direct or through distributors -- Model # (example E21) - maximum of six counters each of nine wheel capacity (9 wheels adding, 8 wheels balancing) with one list bank having 10 numerical bars, and six banks for listing and total printing having 9 numerical and 1 symbol bars' (this from the Build table, which lists other Models).

'During normal card passages through the feed, electrical impulses are conveyed from the card holes to various adding and list-printing magnets. On total-taking, however, the feed is stationary and, therefore, these impulses have to be created by the emitter and conveyed by the upper counter commutators to the print unit. With the Rolling Total Tabulator this emitter supplies the impulses also for transferring information from one counter to another...'