|Name and Model Number||Post 1466 Ritow Manifold |
|Country of Origin||Made in Germany for Frederick Post Co. of Chicago|
|Date of Manufacture||1925 -1931|
|Front Scales||1st half A [2nd half B inverted 1st half B inverted] 2nd half A|
|Back Scales||Back of slide: C & K --- Back of rule: Constants|
|Scale Length||1 m (two 50 cm scales folded)|
|Type of Rule||Slide Rule|
|Construction||Closed-frame mahogany with celluloid laminate scale surfaces. 52.8 cm x 3.6 cm. Frameless cursor marked Germany. Slide friction-adjusting mechanism like that of Dennert & Pape.|
|Area of Use||Generic|
|Comment||Both "Made in Germany" & "Frederick Post Co." engraved in well beneath slide. Maker most likely Dennert & Pape.
Very unique extended scale arrangement of half & inverted scales to achieve a 1-meter long scale on a 50-cm slide rule.
Scale arrangement patented by Herman Ritow for Frederick Post Co.
|Donor||Collection of Ed Chamberlain|
(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.|