#astronomy
James Ferguson's 'Luminarium', a very rare card #volvelle (~1760).
For any date, the volvelle provides the duration of the semi-diurnal arc, or half-length of the day, from which you can find the sunrise/sunset times (for London) by adding or substracting from noon.

If you know the age of the moon for a given date (from an almanach), scales B & C help you find the Moon's time of 'southing' (crossing the southern meridian), and also the average moorise/moonset times by adding or substracting from the southing.

My reproduction, from the printout I made, for latitudes 42 to 52°N.
It seems that the National Museums Scotland has a copy. From its description I guess it could be different from this one.

The 'New Astronomical Instrument', by 🏴󠁧󠁢󠁳󠁣󠁴󠁿 James Ferguson (~1750). A paper model. #volvelle #astronomy

A star chart is visible through the oval opening which represents the horizon for the latitude of London.

Setting the date you can see the visible night sky throughout the year.
With the calendar and the hour wheel, find the times of sunrise/sunset, moorise/moonset, also for drawn stars.
You can also read the 'southing' of stars and the Moon, and their meridian elevation.

Apparently less famous than his 1740 Astronomical Rotula, but more simple to use (well... for the moonrise & moonset it's a bit tricky!).

The lunation scale gives you the dates of New and Full Moons, 1st and 3rd Quarters for the next decades. Even their weekday!

https://fotograrte.tumblr.com/post/740930932638384128/combinaci%C3%B3n-de-nocturnal-volvelle-lunar-y

#Nocturnal #Volvelle #Mareas #Astrolabio #SigloXVI #JuandeRojas #Ciencia #AmerigoLeonae #Navegación #Castilla #España #progresotecnológico #Geometría

Here's a VERY Rare Book!
Dare I say.... a UNICORN?

#volvelle #interactive #popup
#NewberryLibrary #NewAcq

Whatever, #spellingbee.

#volvelle