Thinking that I cannot be the first to see that Delamain and not Oughtred invented the slide rule I found the following article: http://mathshistory.st-andrews.ac.uk/Biographies/Delamain.html which in

Hi, I updated the content document in https://groups.io/g/sliderule/files/AntiqueRules/DelamainEdition2 This second edition seems to be made of different books; some pages are identical and some infor

Mark, I am not sure how your question is meant respectively I had to look what stands on the slide rules... With respect to usage of standard P scale however it is always like this: The easiest exampl

#Faber

Thanks Colin, for bringing up this literature. I will try to access it and work through. I "scaned" "Juglers or Schollers?: Negotiating the Role of a Mathematical Practitioner". This supports my "eval

Colin, I also went through the other both. In short: there is no contradiction to my findings. WILLIAM OUGHTRED'S 'CIRCLES OF PROPORTION' AND 'TRIGONOMETRIES' by P.J.WALLIS: This paper is about dating

Alan, thanks, that makes sense. Then according to modern counting grammelogia was published in Jan 1631; the Kings's patent is from Jan 4th 1631 and the story where Delamain met Oughtred was some week

Hi, today, I reread Cajoris part on the Delamain / Oughtred twist. In the past I mainly "overread" it because being so boring. He parallels Oughtreds and Delamains writings and comes to the conclusion

Hi, I struggled with another part in German wikipedia. I looked for Partridge's book and found it to be in 1661. This date is also used in Cajori. I read the part where Partrige describes the sliderul

PS I forgot to mention from which book of Cajori I took the citations. There is the book dating from I think 1909 / 1910: A History of the Logarithmic Slide Rule and Allied Instruments which states al

John and Tom, in the past Delamain was not in the scope of many who collected slide rules. In the slide rule museum Delamain is even not mentioned. All who go into deepness with Delamain at least must

Karl, isn't publishing not also a good? Not for the sake of being the first, but for the sake that others can make use of it? Aren't the primary reasons for not publishing in most cases in industry to

Tom Am 17.05.2020 um 23:20 schrieb Tom and Lu Wetmore via groups.io: One citaton that I find immediately (it is cited in Cajori (1920), you'll find it there easily) is that: "moveable circle and a thr

Tom, Am 18.05.2020 um 15:57 schrieb Tom and Lu Wetmore via groups.io: Hm. I needed to look for the citation, but I believe that Delamain did not know anything about Forster. Delamain studied at Gresha

Hi Tom, Am 18.05.2020 um 17:22 schrieb Tom and Lu Wetmore via groups.io: Unfortunately yes; the only, and this is what I cite, is Delamains report about the conversion with Oughtred at that walk. This

Hi, I found an interesting sliderule that I never was aware before. It partially fits to Delamains descriptions of his "multi-ring" slide rule: http://nms.scran.ac.uk/database/record.php?usi=000-100-1

Hi, does anybody know how a "Sector" works for the most important calculations and can teach it? I saw the use section in English wikipedia, but this is a little too short for me... Seemingly there is

Thanks Andreas, your link is about gunter rules; they mainly work the same way as normal sliderules with the exception that the equivalent distances for the numbers are taken by compasses and added/su

Thanks to all of you for sending all the links! I will work through the links. It will take a while until I know something for now knowing nothing... Best regards Andreas Am 20.05.2020 um 02:39 schrie

Yes, very fascinating, thanks. Unfortunately these are not meant for mathematical calculating. On the other hand they also show advantages; mainly that it is not needed to measure the exact lengths fo

Hi, thinking in different sets of tick marks from rough to detailed, I could fancy that it made sense for virtual sliderules to have different levels of details at different zoom factors, just if you