No-one likes general adverts, and ours hadn't been updated for ages, so we're having a clear-out and a change round to make the new ones useful to you. These new adverts bring in a small amount to help pay for the board and keep it free for you to use, so please do use them whenever you can, Let our links help you find great books on glass or a new piece for your collection. Thank you for supporting the Board.

Author Topic: What are these Molineaux Webb glass balls for?  (Read 1610 times)

0 Members and 1 Guest are viewing this topic.

Offline Anne

  • GMB Tech Support Manager & "Board (never bored) Dame"
  • Global Moderator
  • Members
  • *
  • Posts: 13871
  • Gender: Female
  • I has a stick to poke the server with yes!
    • Glass trinket sets
    • Cumbria England
    • My Glass Collection
Re: What are these Molineaux Webb glass balls for?
« Reply #10 on: July 11, 2010, 07:29:58 PM »
The biggest problem with them being balls from the Campbell-Stokes type sunshine recorders is the size, as the smaller the ball the smaller the card the data is burned onto, so I would think it calls into question the accuracy of any readings if they are too small.

I've found the specs from versions still being made and that gives the size of the sphere as 101.6mm (i.e. exactly 4") diameter, the same as the ones in David's Chance advert, and those offered for sale today say they are made to a British Meteorological Office specification (so in this instance I think size does matter Christine  :24: :))

However, searching through the Science Museum online stuff I found a page here: which shows a variety of instruments from an exhibition in 1885, one of which might have a smaller ball: see image, second item from left top row. Sadly the writing is too fuzzy to read the caption underneath this item.

It might be worth Neil contacting the NMSI and asking if they have a higher resolution copy of this image and what that second item is... and it'd be also worth asking the Manchester Art Gallery if their balls are attached to those stands or if they are separate.

Cheers! Anne, da tekniqual wizzerd
~ Glass Trinket Sets ~ GlassLinks ~ GlasSpeak ~ GlassGallery 
 ~  Glassoholic Blog ~ Glassoholic Gallery ~

Offline David E

  • Author
  • Members
  • ***
  • Posts: 3912
    • Heart of the Country, England
Re: What are these Molineaux Webb glass balls for?
« Reply #11 on: December 20, 2015, 06:07:38 PM »
Having just revisited this topic, as there were so many different sizes, going down to 'powder' (almost), then they could have been what became known as Ballotini beads. These had a wide range of uses, such as a coating for reflective road signs, cinema screens, and the largest known were used for storing blood plasma - not sure what size these were, but I imagine the idea was to prevent coagulation.

Sizes quoted on the original patent of 1943 (US2334578, R H Potters) were 0.008-in to 0.055-in*. However, all this is superfluous as it  post-dates the Molineaux Webb spheres, unless MW never patented their idea?

*In Monopoly money that's 0.2032 to 1.397mm
► Chance Additions ◄
The 2nd volume of the domestic glassware of Chance Brothers
Contact ► Cortex Design ◄ to order any book


SMF spam blocked by CleanTalk
Look for glass on
Visit the Glass Encyclopedia
link to glass encyclopedia
Look for glass on (us)
Visit the Online Glass Museum
link to glass museum

This website is provided by Angela Bowey, PO Box 113, Paihia 0247, New Zealand