Here are the front and back cover from a Lawrence Slide Rule Instruction Book, last copyright 1940. The Lawrence Engineering Service was in Peru, Indiana. Click the thumbnails for a larger image.
The front cover states "How to get correct answers instantly without pencil and paper"
The back cover shows some of the occupations, including "housewife" and "farmer", who "need a slide rule".
And the inside front cover states: "Anyone who will apply himself to the operation of the slide rule and will make its use a practical habit while at work, study, or leisure, will find himself richly rewarded in the saving of time and energy -- to say nothing of the satisfaction that comes from the mastery of 'Man's most useful tool.'"
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