Stanley’s first planimeter (part 1)
November 16th 2023 marks the bicentenary of Jakob Amsler-Laffon's birth - at least according to the more trustworthy sources - so it seemed only fitting to save a rather special…
Stanley-Amsler double act
Like the previous post's Amsler Type 6 with its added spikes for engine indicator diagrams, today's planimeter is another general purpose instrument with a special trick up its sleeve. Patented in…
Happy 200th Amslerversary!
While doing a bit of planimeter research, I noticed that Wikipedia gives the date of 11 November 1823 for Jakob Amsler-Laffon's birthday - 200 years ago today! Amsler was a…
Mechanical Pencil Month – Day 20: Mordan’s Bicentennial
The final day of our countdown has arrived which means it is time to go back to where it all began. By that I don't just mean Hawkins and Mordan's…
Mechanical Pencil Month – Day 18: Rotring multi-pencils
One type of sliding pencil that did not get a mention in yesterday's entry was the multi-colour everpointed type, made by Sampson Mordan among others. These particular models always appear…
Mechanical Pencil Month – Day 17: Slide rules, OK?
Another Slide Rule Saturday rolls around (whatever happened to the last one?) and having already used up my only slide rule pencil as well as my only pencil with slide…
Mechanical Pencil Month – Day 16: Cone v. Cylinder
Over the last few days, the question of point shape has come up more than once. There was the Staedtler REG with its throwback conical point in an age of…
Mechanical Pencil Month – Day 13: Staedtler REG
Unlucky for some, the Staedtler 925 85 REG is one of those pencils that elicits mixed opinions. Released by Staedtler's Japanese division in 2004, its short name comes from the…
Mechanical Pencil Month – Day 12: Twelve leads a-leaping
For the twelfth day of Christmas Mechanical Pencil Month, I present a whistlestop tour of twelve lead refills from my collection of [insert large number here]. They have been arranged…
Mechanical Pencil Month – Day 11: Side-knock pencils
Today's post takes a quick look at three examples from the small sub-genre commonly referred to as "side-knock" pencils. Unlike most conventional mechanical pencils in which the lead is advanced…