Unidentified hallmarks on a pocketwatch. Can you assist.

These hallmarks are on a Pocketwatch i own but i am unable to identify them. Can you help.
The presentation date is 1899 and it is a Longines Minute/second recorder chronograph.
Type 19.73N All individual parts of the casing inc. body have the same marks.
Hallmark1.jpg

Switzerland

and period 1882 to 1934. The mark was used for 875 or higher silver contenth. In your case 935