Notes: "This is an early Faber Castell model 378 Electro slide rule. The sure sign that this is an early 378 is the “W” mark at the right end of the C scale. This ‘gauge point’ is necessary for calculations involving both log-log scales because the two log-log scales do not use the same base. Later models of the 378 and all future Faber Castell Electro slide rules used a consistent base (e) across their log-log scales. The model 378 moved the log-log scales from the beveled edge of the 368 to the upper and lower stators on the front face. This slide rule features typically robust Faber Castell construction, with brass bars inset into the wood to allow the owner to bend (carefully!) the rule back to straight should it ever warp, with the brass bars maintaining the new shape. "
