I have now retired from the University but have retained honorary fellow status as I have a few things to finish off. It is not clear how much longer this blog will exist.
Until February 2026 I was a lecturer (full title: Reader in Atmospheric Science) in the School of GeoSciences at the University of Edinburgh. My research was on remote sensing of the atmosphere, mostly using the MLS instrument. My contact details are here and my official research page is here. My publications list will give you the full details of my research work. My ORCID is 0000-0003-0747-1457
The purpose of this blog is for me to write about stuff that isn’t strictly work but is connected with it in some way. There are posts on various aspects of atmospheric science, Earth science and the teaching of science. But quite a lot of stuff has crept in about what is growing in my garden, Free Software advocacy, scientific computing etc. There is a whole subgroup of “classic lump” posts on ascents of small and insignificant mountains.
This blog was originally hosted at https://hughpumphrey.wordpress.com . At the time I started it, the University did not provide a blogging platform. I moved the blog here because https://blogs.ed.ac.uk/ was introduced, and because WordPress had increased the number of flashing adverts shown on the original blog to a ludicrous level. Note that a lot of the links from one blog post to another still point back to the old site. I may continue fixing these as I come across them.
You can follow me (@hughpumphrey.bsky.social) on BlueSky . (I do have an account on X (a.k.a. Twitter, @HughPumphrey) but I almost never use it these days.
Dear Hugh
I came across your blog on Benchmarks (Feb 2023) and enhjoyed reading the article.
However, the picture you include of a “Pivot” mark is not an OS mark. I am not sure exactly what this is but pivots are quite different.
Pivots tend to look rather like rivets without the metal pin. In fact the pin was quite frequently added to a pivot to convert the mark into a rivet.
I have been told that in a pivot BM the arrow will point to a small depression into which a large ballbearing was placed and then that was used in the levelling process.
A good example (of which I am rather proud) of a pivot can be found in Edinburgh (https://www.bench-marks.org.uk/bm177920).
Thanks for the entertaining read.
Regards
Mick Rye (AKA WeTRyehard)
I updated the post to include a photo of the actual pivot, after being directed to its location by someone else. It is a very old mark; I suspect that the standard design of pivot had not been settled on at the time it was cut.