My father bought one of these in the early 1960s for college (in its Frederick Post incarnation, which seems to have been called a Post 1491), since he was studying chemical engineering for a while, and I spent some time playing with it as a kid. I think he has it now. I remember being puzzled by its scales and, of course, it was hard to look up how to use the ones on the back because they were pretty much unique to this model. The most unusual thing about it for a rule this fancy is that on the front, it has a set of log-log scales but no trigonometric scales--not even the ones that exist on basic slide rules. I guess chemists have to raise things to powers a lot but not do a lot of trig.
This is a great assistance to my recent research, thank you. Do you know of a book or textbook on slide rules; seems to be almost impossible to find. Im an engineer so looking for dec & log but its becoming a lost art the old slide rule
Thanks for your kind comment. There is a large free library of manuals and SR textbooks available in PDF format at the Sliderule museum: www.sliderulemuseum.com/
My father bought one of these in the early 1960s for college (in its Frederick Post incarnation, which seems to have been called a Post 1491), since he was studying chemical engineering for a while, and I spent some time playing with it as a kid. I think he has it now. I remember being puzzled by its scales and, of course, it was hard to look up how to use the ones on the back because they were pretty much unique to this model. The most unusual thing about it for a rule this fancy is that on the front, it has a set of log-log scales but no trigonometric scales--not even the ones that exist on basic slide rules. I guess chemists have to raise things to powers a lot but not do a lot of trig.
I can see these as EXTREMELY useful today, having taken Chemistry.
This is a great assistance to my recent research, thank you. Do you know of a book or textbook on slide rules; seems to be almost impossible to find. Im an engineer so looking for dec & log but its becoming a lost art the old slide rule
Thanks for your kind comment. There is a large free library of manuals and SR textbooks available in PDF format at the Sliderule museum: www.sliderulemuseum.com/
www.sliderulemuseum.com/Manuals/TheSlideRule_AlfredSlater_306pgs.pdf
@@jkneathery Brilliant! I shall check it out today, thank you so much. 😊
I'd like to find one of these to purchase.
A few Hemi 257s are currently listed on eBay. They are offered for 100-$150.
I own a Hemmi No. 259D "Expert Mechanical Engineer".
Thank you so much!
Awesome!
It's a calculator, but it's made out of bamboo!