SLIDE RULES
BY  DAVID A. DAVIS
ARCHIVE SITE
exclusive on-line slide rule content since 1998!
  It's hard to believe, but as of March 2008 I will have had slide rule related content on my website for TEN YEARS! Actually, the first early articles appeared on an older incarnation in 1996, but my brother Will and I count March 1998 as the real launch of our "new" sites. We're planning a couple pages to show some of the fun things you won't see very often, to thank some of the people who have helped along the way, and to share some stories too. Stay tuned for those things, and also some updates concerning R/R brand rules too! I recently bought a Ricoh 1051S, a model not sold here in the US, and it spurred me to look harder for foreign sold variants. I found a few, so I'll put those up for those who might be interested. Some of the rules are quite interesting, so that should be fun.
    The K+E DORIC archive is still in the works too, just delayed by other research projects which have taken more of my time lately. And, I have a few more things to go into the DIETZGEN archive too. I know, updates are infrequent here, but as this is primarily an ID archive site, well, most of that doesn't change unless I find an error!! Or something new, better yet!
HOW TO USE THIS SITE
  This site is intended to be a ready-reference for type identification. The most frequently seen types for both Relay/Ricoh and Dietzgen (the duplexes for Dietzgen anyway, which are more common and collectible ) are all listed below. For Dietzgen, type i.d. is easy, but not so for Relay/Ricoh.
    Most of the re-brandings of R/R types are listed along with THE RULE THEY WERE MODIFIED FROM ORIGINALLY. So, from our list below, you will be able to navigate through the various types, and on each page several rules will be listed in text form, along with any known modifications and re-brandings. Many rule types have direct links to the appropriate images in the archives too.
    Last, take a look through our image archives, for id tips, and to see some unusual rules. Some age estimating information is also given here, and highlights on construction changes over the years. There's LOTS OF INFORMATION in the image archive!
     Additionally, it should be noted that here you will find the ONLY on-line reference for the rare NIKKEI brand slide rules. Few exist, and what I have been able to learn about them is all here.
INTRODUCTION TO THIS WEBSITE
RELAY/RICOH ARCHIVES 
...pages of model types, manuals and other info.
UPDATED!! 150, 151, 153, 154, B-1734, 158, 156, 159, B-1
...also an introduction to US Relay/Ricoh rules.
157, B-1725, 1737, 551,( Darmstadt type), 107
UPDATED!!
SIX PAGES!
252 (152), 102S, 550, 450, Nikkei 510
Image archive
1957 Relay manual/catalog
...with pictures!
1959 Relay manual/catalog ...with pictures!
The slide rules of S.I.C.
...with pictures!
NIKKEI SLIDE RULES!!
TWO PAGES!
Brand notes
brief notes about US distributors
DIETZGEN ARCHIVES Currently listing all known duplex types, with and without log-log scales!
1731, 1732, 1733, N1733 (N1731), N1732, 1734
B-1734, G-1734, 1738M, 1736, 1737, 1735, N1725, B1725, 1741
IMAGE ARCHIVE
1739L, 1779, 1773, 1778, 1744, 1746
1749M, 1743, 1745, 1751, 1776, 1771, 1768P, 1767, 1757
Keuffel and Esser's DORIC SERIES SLIDE RULES archive
COMING SOON...
DAVIS BROS. ANTIQUES IS CELEBRATING TEN YEARS OF FREE ONLINE  RESEARCH CONTENT! HERE ARE SOME OF THE PEOPLE I'VE MET AND THINGS I'VE  GOTTEN ALONG THE WAY...
COMING SOON...
DAVIS BROS. ORIGINAL SITE!
Follow this link to see our original mega-site! MORE SLIDE RULES, featuring magazine type articles, as well as links to all the other sections or our site. Typewriters, sewing machines, even railway locomotives! Also links to many other sites, including our YAHOO LOCOMOTIVES GROUP! Changes are underway for our old site, so stay tuned. (Some content will be moved here.)
TOP SLIDE RULE LINKS WORLDWIDE
A page of links to the very best slide rule sites in the world! Buy, research, discuss, whatever!
NEW!! LOCOMOTIVES@DAVIS BROS.
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