American Levels and Their Makers
Stanley began to produce small wooden machinists' levels at about the same time that they introduced the No. 96. Like the No. 96, the No. 98s were brass bound rosewood and some of them were of laminated construction. Although they had full brass end caps from the beginning, the early versions of this level (like the two shown here) had a nailed on edge binding. Dovetailed bindings would await the expiration of the Stratton Bros. patents.
The two levels pictured here are very short, 9" and 6". But even at this length, Stanley incorporated the groove along the side. This groove was a patented feature (June 2, 1891) whose function was to improve the users ability to grip the level and it was termed the "Hand-y grip." The levels also incorporate three other new patents (2-23-1892, 2-19-1895, and 6-23-1896). These patents as well as the one for the "Hand-y Grip" had been awarded to Justus Traut. The first two dealt with adjustable vials while the 1896 patent concerned vials that could be reliably marked with black lines to assist the user in determining when the bubble was centered.
In addition to using ground glass vials, these levels and the No. 96 were the first to employ brass screws to hold the top plate and end plates. Prior to this, the levels used iron screws which were susceptible to rust and interacting with the brass plates they held thereby producing an unsightly black stain. Iron screws could also disintegrate because of rust creating a problem when the user tried to replace a damaged vial. Broken screws required that the hole be abandoned or drilled out, or worse - that the replacement screw would be crooked and could come through the side of the level.