2 diff Slide Rule instruction manuals - Keuffel & Esser

Description

2 Slide Rule Manuals
I never could figure out how to use my Slide Rule in High School - and looking at these manuals, I can see why.  So complicated!!  These are complete with diagrams and full instructions.  Both published by Keuffel & Esser, the first one pictured measures approx. 5" x 8" and contains 90 pages.  Besides the basic instructions, there are very complicated problems, and instructions for using your slide rule for the force of the wind, discharge of water, etc.  Cover showing slight soiling, inside is perfect.  Dated 1924.
Second booklet is 15-pages and has basic instructions.  That one is of very thin paper.  Very good condition. Dated 1936
Postal rates have recently increased yet again, and I am beginning to need to charge for shipping, which will be by 1st class mail in a plastic sleeve with rigid backing. If you would like any other shipping options, you need to contact me before paying for the item.   Payment includes required ebay tracking; and unfortunately I've had to raise my recent item prices a bit to accommodate the required tracking expense.   If you wish other postal services, you need to let me know before paying for the item.   In general, I have found the post office to be excellent.  But every once in a while items seem to take the long route to a customer's home.
I will always combine shipping, if I can, for items purchased at the same time.  If you have purchased multiple items, please wait for my note or corrected invoice before paying for the lots. The international postage shown is for Europe - please inquire if you live in Australia, the Far East or Africa.  Rates may be higher, especially if this is a heavier item.
Please be sure to contact me if you have any questions.