A Guide to Illinois Watch Co. size 12 Watches, Grade 505.
Run.
Date
From
To
Total
H/O
Jls
Adj.
Run.
Date
From
To
Total
H/O
Jls
Adj.
1
1914
2,640,601
2,641,000
400
O
17
Adj.
14
1918
3,401,501
3,401,700
200
O
17
Adj.
2
1915
2,799,531
2,799,540
10
O
17
Adj.
15
1918
3,413,901
3,414,000
100
O
17
Adj.
3
1916
2,889,601
2,889,900
300
O
17
Adj.
16
1919
3,461,901
3,462,000
100
O
17
Adj.
4
1916
2,890,201
2,890,500
300
O
17
Adj.
17
1919
3,468,801
3,469,000
200
O
17
Adj.
5
1916
2,901,301
2,901,600
300
O
17
Adj.
18
1919
3,509,701
3,510,000
300
O
17
Adj.
6
1916
2,904,601
2,904,700
100
O
17
Adj.
19
1919
3,537,701
3,538,000
300
O
17
Adj.
7
1916
2,945,851
2,946,300
450
O
17
Adj.
20
1920
3,618,701
3,619,000
300
O
17
Adj.
8
1917
3,089,501
3,090,000
500
O
17
Adj.
21
1920
3,620,001
3,620,200
200
O
17
Adj.
9
1917
3,116,501
3,116,700
200
O
17
Adj.
22
1920
3,664,001
3,665,500
1,500
O
17
Adj.
10
1917
3,130,901
3,131,000
100
O
17
Adj.
23
1920
3,736,501
3,737,000
500
O
17
Adj.
11
1917
3,144,501
3,145,100
600
O
17
Adj.
24
1920
3,788,201
3,788,700
500
O
17
Adj.
12
1918
3,382,801
3,383,200
400
O
17
Adj.
25
1921
3,884,001
3,885,600
1,600
O
17
Adj.
13
1918
3,401,001
3,401,400
400
O
17
Adj.
  Total
9,860
 
Name
H/O
Estimate
Name
H/O
Estimate
Ariston Rated USA
17 Jewels O.F.
100
Hallmark
17 Jewels O.F.
8,850
Illinois
17 Jewels O.F.
400
     
Grade 505 runs.
Grade 505 Movements found to date.
Serial numbers used on this page by the kind permission of
Russell W Snyder
Last update 12/22/2015 .
Grade 505,
17 ruby and sapphire jewels adjusted, manufactured from 1914 to 1921 a total of 9,860 movements in 25 runs make up this grade. Model 4 size 12/14
open faced; bridge movements of medium quality, double roller and patent micrometric regulator.

Observations,
The majority of movements have broad striped pattern demaskeening named Hallmark and Ariston rated. The remainder are bright striped pattern
and named Illinois. The size 12/14 movements have a size 12 bridges and size 14 pillar plate and have a stretched enamel dials that are not recessed
into the pillar plate, they require special cases. Hallmark watches were made for United Jewellers and come in hallmark cases, Ariston rated watches
were made for Marshall Field and the cases are marked Ariston with the M F & Co. logo. Illinois watches have The Springfield Watch marked on the
cuvette.

Variants,
Two types of escapement bridges can be found, most of the movements have the two fingered bridge except for the Ariston rated models that have a
full plate escapement.

Description,
17 ruby and sapphire jewels; oreide settings; adjusted to temperature; spring tempered compensating balance with timing screws; hardened and
polished steel escape wheel; sapphire pallets and jewel pin; polished gold center wheel; patent Breguet hairspring; micrometric screw regulator; safety
screw center pinion; concave and polished winding wheels; safety recoil click; demaskeened broad striped pattern; gold inlay engraving; unusually
large dial is a special feature of the watch.
Image from run 22.