Jeffers Calculator, American ready reckoner for nu

Made:
1907 in United States

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Science Museum Group Collection
© The Board of Trustees of the Science Museum

Science Museum Group Collection
© The Board of Trustees of the Science Museum

Science Museum Group
© The Board of Trustees of the Science Museum

Jeffers Calculator, American ready reckoner for nutritive ratios, by Henry Jeffers, 1907

Like the triangular rule, this instrument is for someone who loved figures. Henry Jeffers was a New England dairyman and republican politician. He devised this ready reckoner in 1907 to compute the right mixtures of feed and ingredients for livestock nutrition. About 60 slides, each for a different animal foodstuff, can be slid into the ‘calculator’ on the right-hand side of the open box. For any number of pound weight, the dry matter, ‘proteids’, carbohydrate and fat can be read off. There is also a cost calculator.

Details

Category:
Mathematics
Object Number:
1990-685
Materials:
brass, ivory and wood
type:
ready reckoner (medical)
credit:
Auction Team Koln