• 455 Martinson, Los Angeles
  • 8 (043) 567 - 89 - 30
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  • Koch, Huxhold & Hannemann (KHH) - made surprising System Korte slide rule that does addition & subtraction
  • Smallwood Folding Shoe Sizing Stick in metric for French shoe sizes 10-48 in increments of a Paris point (⅔ cm)
  • Lawrence MIT Antenna slide rule for radar antenna performance was classified during WWII by UK & US governments
  • ALRO-made ruler unusually with a cursor for analysing ECG printouts of the cardiac Sinus Rhythms
  • Hatters Gauge - for measuring the size of a hat but unusually calibrated in metric & imperial
  • Glovers Rule - for measuring the length of a glove in imperial inches
  • Unusual non-logarithmic QR 41 military model by Dennert & Pape (D&P) for training anti-aircraft gunners
  • Colour combinations slide rule made by German WH-Wohnen for Interior Designers
  • Professor Fuller’s Drum Calculator from 1878 - made by W.F. Stanley
  • Modern wristwatch with slide rule bezel calculator made by German maker Kienzle
  • Ruxton made Multi-Vider combined drop-lead pencil & slide rule
  • Rare Otis King Model N for Retail & Monetary with white scales (422 & 424) on a black background
  • Darnley’s Rotable Lightning Calculator/Pencil Case calculating aid
  • Makeba made Kombinator combination pencil & slide rule
  • Rare Carbic-made Fischer Calculator slide rule
  • Specialist slide rule for a national home cable radio broadcasting system offered in The Netherlands from 1930 to1970
  • Smallest drum (≈ 2.4m) made by renowned Swiss maker LOGA

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Search results: Click on any Model listed in the leftmost column (or its image) for the full specification OR hover over its "Thumbnail" image (if shown) for a pop-up enlargement

You searched for: Dennert & Pape (D&P)
ModelTypeMaterialCommentsThumbnail
14 Electro wood/celluloid veneers

cm scale in well + 3 adjustment screw in bottom side edge

Dennert & Pape 14 Electro
D 2/28 Enhanced Mannheim - early wood/celluloid veneers

Railway track scales + cm scale & D&P D.R.P. no. 126499 in well & 3 adjustment screws in bottom side edge +- conversion table & 2 open windows on back

D 2/28 Enhanced Mannheim - short wood/celluloid veneers

Short stock length (possibly because shortage of raw materials) with railway track scales + cm scale & D&P Altona & “Patent” in well of stock - conversion table + 2 open windows on back

D 9/28 Rietz wood/celluloid veneers

3 adjustment screws on bottom side edge - conversion tables on back

DUPA D14.15 Pocket Electro wood/celluloid veneers

Company NAW & model details in well & 2 adjustment screws in the bottom side edge + table of conversion factors on back ​

Dennert & Pape DUPA D14.15 Pocket Electro
DUPA Line Loss & Voltage Drop Calculator Electro poly-slide (2) wood/celluloid veneers

Copyrighted & patented (US1560599) by Charles C. Moler in 1925 - special commission for The Potomac Edison Company, Maryland, USA (Moler’s employer) ​- 4 adjustment screws in top side edge - besides preventing voltage flicker on electrical distribution lines it could save money by avoiding expense of higher grade of cable when not needed - read more ....

Dennert & Pape DUPA Line Loss & Voltage Drop Calculator Electro
DUPA S.90 Rietz wood/celluloid veneers

Possibly an early special commission for H. Linke - PERTODO = D&P trademark for free-view cursor (they wanted RERTOTO from the Latin word “totus” but had to change to PERTODO) - 4 adjustment screws on bottom side edg​e - conversion tables on back

GWR Desktop Military Naval Artillery plastic

Instruments for German armed forces during WWII used codes to hide maker’s identity - gwr​ = D&P + besides solving normal artillery-related distance problems, this naval version also takes into account drift of a moving vessel

Dennert & Pape GWR Desktop Military Naval Artillery
I Enhanced Mannheim wood/celluloid veneers

Table of conversion factors on back

I Lilliput Enhanced Mannheim wood/celluloid veneers

D&P in well + ​Inch & cm scales on back

I Pocket Enhanced Mannheim wood/celluloid veneers

cm scale & D&P & D.R.P. No. 126499 in well of stock

I Pocket Enhanced Mannheim - early wood/celluloid veneers

D.R.P. No. 126499 in well of stock + inch & cm scales on back

IV Desktop Enhanced Mannheim wood/celluloid veneers

IV = model with 4 adjustment screws in bottom edge - railway track scales - cm scale in well of stock​

Präzisions-Kubus-Rechenstab Squaring long-scale wood/celluloid veneers

Uncommon & unusual model with just root & trig scales (all long scales) - one open window with cursor line in back on right​ ​

Dennert & Pape Präzisions-Kubus-Rechenstab Squaring long-scale
QR 41 Desktop Military Artillery Squaring plastic

QR = “Quadrat-Rechenschieber” - commissioned by “Gebr. Wichmann” (stamp in well) - probably classroom training aid for anti-aircraft gunners - layout consists of two pairs (upper set 0 - 50 & lower set 0 - 15.8) of non-logarithmic independent root scales (no interaction) derived from a set of tables by German Peter Timpenfeld & first published in 1888​ - non-conventional use of a cursor purely for positional summing of the squared values

Dennert & Pape QR 41 Desktop
S 6/28 (System Rietz) Rietz wood/celluloid veneers

DRP No. 126499 in well of stock & 3 adjustment screws in bottom side edge + conversion tables on back​ + 1 cursor window