Barbotheu Slide Rule, 17 Rue Beranger, Paris.
Depose Pratique Slide Rule
Maurice Damien Universal Slide Rule
Graphoplex 612.
Graphoplex 612. This is an advertising slide rule for Schlumberger. The scale labelling has the standard pattern instead of the Graphoplex pattern in the 612 above.
Slide Rule advertising The British Thomson-Houston Co.Ltd. Rugby, England. I believe that this is a Graphoplex. The scales themselves are identical to those on a Graphoplex 615 except that the length scale is in Inches instead of Centimetres, the style of labelling using B^3 instead of K for example is also used by Graphoplex. For these reasons I am placing it with my other Graphoplex rules. There are no manufacturer's marks to prove its origin therefore please regard this as my personal opinion not an absolute fact. British Thomson-Houston were a manufacturer of steam turbines at the outbreak of the Second World war and provided facilities to Frank Whittle and Power Jets in the early years of the Jet Engine. This is referenced in chapter 4 of 'Frank Whittle Invention of the Jet' written by Andrew Nahum. Incidentally this book also contains two illustrations of Frank Whittle with a slide rule. A web search indicates that Whittle's slide rule is in the Churchill Archives of Churchill College, Cambridge.
Graphoplex 620.
Graphoplex 630, Geometre-Topographe. Surveyor's Slide Rule. Donated by Gonzalo Martin.
Graphoplex 640.
Graphoplex 643.
Graphoplex, Koh-I-Noor, 650 Electro.
Graphoplex, 690a Neperlog.
Graphoplex, 694a Technilog.
Graphoplex 1600.
Graphoplex 1614.
Graphoplex Gaz de France. Pipe Capacity Slide Rule. Donated by Gonzalo Martin.
Graphoplex Gaz de France. Pipe Capacity Slide Rule.
Graphoplex Pipeflow. Specially designed and divided Slide Rule for calculating velocity, diameter and quantity of water in pipes.
Shell Stack Loss Slide Rule. The Graphoplex name is not visible on the rule but it is the probable manufacturer. Stack losses are heat losses and unburnt fuel losses in chimneys and flues.
Guedon, BOX.223, Camden, New Jersey, Made by Unis MARC, France. 5"//A[B,C]D
MARC, No.4.
MARC, Electricien No.5.
MARC, No.6.
MARC slide rule with interesting Callender's Cable & Construction Co. Ltd diagram on the back.
Tavernier Gravet Slide Rule.
Tavernier Gravet Pipeline Slide Rule.
