|Name and Model Number||Keuffel & Esser 4065T |
with Column Cursor
|Country of Origin||USA|
|Date of Manufacture||c. 1915|
|Front Scales||A [B S C] D|
|Back Scales||A [BI T CI] D L|
|Scale Length||20 cm|
|Type of Rule||Slide Rule|
|Construction||Celluloid scale surfaces on mahogany, duplex slide rule, with "column" framed glass cursor.|
|Area of Use||Generic|
|Comment||This example has "decimal keeping" mnemonics and the owner's name neatly engraved on the front.
The mnemonics assist the user in keeping track of the position of the decimal point.
This is especially valuable for problems with multiple operations.
|Donor||Collection of Ed Chamberlain, USA|
(Click Picture for Details)
|In conjunction with our 'donors' we assign a rarity rating to each item, based on the system devised by Herman van Herwijnen|
|(1929 - 2004), renowned Dutch collector, author, and creator of Herman's Archive, a collection of 5,000 slide rule images on CD.|
|• RR = Rare - 1 of 25 collectors has one; it may take a year to find an example in the marketplace.|
|• RRR = Very Rare - only a few known to collectors; may be several years before it comes up for sale.|
|• RRRR = Extremely Rare - a museum piece; unlikely that an example will come up for sale.|