Independents

David Walter
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Answers

1;The wheel in question is indeed the Equation of Time wheel as Don correctly surmised. This wheel turns once per hour, the blued steel mean time minute hand is fitted to the square while the gold Equation of Time hand is fitted to the steel pinion which is engaged by the two racks. The steel lever on the right is disengaged by a spring lever mounted on the plate once per hour for about 90 seconds, this unlocks the ratchet wheel while the tab on the upper of the two racks is free to brush against a flag attached to a pivoted lever to check for any changes. This pivoted lever has a jeweled follower fitted to the other end which is in contact with the equation cam, the cam itself is fitted to a 365 tooth wheel which is advanced one tooth per day. This system allows the train to run without any drag on it other than the few minutes the tab is in contact with the flag, the operation is deceptively simple but very demanding to make.
While this wheel looks quite  large it is only 49mm, the ratchet wheel is 30mm with 130 teeth.

2; French Silvering has a different preparation process and leaves a much heavier deposit of silver on the dial, it also has a different final texture which is a matted effect. French Silvering is very white while English silvering is gray.  It is quite difficult to photograph the French Silvered dial and reveal the finished effect.
 
Below is a direct comparison I did with French silvering on the left and English silvering on the right, the lighting is the same for both dials.