2026 Summer Update

Site Ephemeris, Volvelles, Activities, and the State of the Market

Over the past year, BC Gnomonics has been continually updated with minor tweaks. New museums were added to several instrument pages, quite a few new websites and simulators joined "Activities and Downloads," and a stream of curiosities and short posts continues to populate the Youtube channel (https://www.youtube.com/@BCGnomonics/posts).

This summer, more substantial additions warrant a dedicated announcement. Most notably, a new permanent resource expands the site's navigation bar: Ephemeris.

The logical progression of the planetary position widget found on the astrolabe's instrument page, this new page contains a number of values and references (some updating in real time!) useful to users of scientific instruments. Live planetary positions, a live lunar age value, your own calculated solar to civil time correction, and magnetic declination calculator are just some of the references arranged for convenient use.

The bottom of this page also includes imbedded websites, allowing the in-site use of Alex Boxer's astrolabe, Richard Wymarc's lunar volvelle, and Jan Tošovský's astronomical clock.

BC Gnomonics Volvelle Compendium

Over on "Activities and Downloads," a collection of five original volvelle downloads with accompanying instructions has been added. Most notable among these is (as far as I know) the first publically accesible replica of Peter Apian's Speculum Cosmographicum, or cosmographic mirror. Fascinating as this instrument is, it has also spawned its own instrument page.

These volvelles, where relevant, have been added to their respective instrument pages as free downloads while also being compiled as a set here.

New Astrolabes Hit the Market

Lastly, as it is one of BC Gnomonics missions to uplift the work of modern producers of quality instruments, a brief update regarding the astrolabe market.

On Etsy, Wavytail, StudioBiondi, and astrolabivm have splashed down with impressive new astrolabes.

Wavytail, most recently, has begun producing brass astrolabes availible in both 5 inch and 2 inch models:

StudioBiondi offers a beautifully designed and layered wooden model:

astrolabivm's stock contains a range of acrylic astrolabes, as well as others by makers such as Master Terebrus.

I'm very happy to see a building volume of astrolabe offerings by such dedicated and genuinely invested artists!

BC Gnomonics will continue to evolve via drip-fed updates, so keep an eye out for features—even between announcements. Official content will be posted to this website and to the BC Gnomonics youtube channel (be sure to check out its "posts" tab!), but subreddits r/Sundial and r/Astrolabes serve as supplementary streams populated by myself alongside innovative dialists and astrolabists. Don't hesitate to contribute!

Evan Boxer-Cook

Founder

P.S. I leave for the University of Cambridge in September. This means that updates will be sparse for a period, but it also means that whatever updates there are will be richly informed by the information and collections I will be diving headfirst into!