Glass Slide Sets:
Not only is the Fisherview set unusual in being an offering of glass views from an American company, but it is doubly unusual in being produced in the 6 x 13 cm format. The overwhelming majority of glass WWI stereoviews are 45 x 107 mm. It is likely many original wartime images were shot in the larger formats, but 45 x 107 being the most economical and common, it makes sense most views were produced in this size.
The first box in the set includes a catalog giving a brief description of each plate. On the back cover it explains the set includes six boxes of twelve plates each. It goes on to say additional views could be had. The numbering system, series WA through WF, suggests there may well have been much more extensive offerings. Otherwise, why would they start with "W"? The Scientific Materials Co. in 1925 changed its name to Fisher Scientific, so the brochure at least was printed prior to then.
Reading the current company bio, this product seems a little of an odd diversion for them. They specialized in scientific lab equipment. Perhaps the connection comes from the fact until the war they bought a great deal of product in Europe.