Hello all, Had a great talk with Lindell on this Sunday about this movement. Pulled this out of my drawer after maybe 20 years. Movement reads S.W.Co Springfield Ill. Model 1 full plate grade SWC & Diurnal course train. Pinned roman dail looks great. Nice hands. How rare might this be?This needs a nice home.Will take trades. And any info someone have. Thanks Lindell. TED

Buy the way serial # is 84,242.This is a keywind & Keyset. Put a new roller jewel in it and its been running for the last two hours. Regards Ted

Hi Ted

I am not really sure about this info, without any photos to go by. Illinois made a movement called Diurnal, which was a 18s Key wind & set hunter 7 jewel. Supposedly they made 3 runs from 1876-1878 for a total of 4150. 80001-84100, 84901-85000, 85001-87000

The serial number you listed 84242, doesn't fall into those numbers but we all know the records are not exact.

Your serial number is listed as a model 1 Key hunter Interior grade which was made in 12 runs from 1876-1878 for a total of 10,200. Yours was in run 84101-84300 but the run just before it was a run of Diurnal so perhaps the run numbers are off.

Is your hairspring attached to the balance cock or is it attached to the bridge?

Tom

Just saw this post from earlier this year where Tony had acquired one of these.

https://ihc185.infopop.cc/eve/f...881029912/m/30510149

Tom

Hi Tom. Thanks for the info. The hairspring is attached to the balance cock. Great to hear from you. Regards Ted

Tom, The movement looks just like the one Tony Dukes but mine has S.W.Co and Tony,s has Diurnal.Ted

Ted

Nice to hear from you too!

This is the image from the gold book, EA452A , it says made only in grades SWC & Diurnal.

Tom

Lindell

I had also wondered where the name Diurnal came from, I found where it has several definitions;

Diurnal motion is an astronomical term referring to the apparent daily motion of stars around the Earth, or more precisely around the two celestial poles.

Apparently it is also used as the word daily.

Tom

Wow! This is fun.Thanks Lindell & Tom. Photo EA 452a also says it made with a expansion shape balance ( what is that )?

Ted

I am just guessing but I wonder if they are referring to a compensated balance wheel, ie. a normal bi-metal cut balance?

Tom

Tom, This is not a compensated, its a three arm metal. i have many old Walthams they called them under spung steel balance and it looks the same maybe thats just another name for it. Been watching it running and the hairspring is expansioning just like the old Walthams. Ted

Ted

I was thinking they were saying it could come with either type, the solid 3 arm like yours or the two arm split.

If you look at EA 452 it has the compensated balance but also says it was made with the three arm. Just all guess work on my part