Dang, wish BF would allow longer editing as it would save another post. In perusing over the 1934 Dumaurier catalogue I note Busch Terlux offerings in 24, 18, 15 & 10x. The 15x, that I own, is listed as 52.5m/m objective lens, Light Transmitting Power of 12.25, Fiels of 59.5 yds, Height 8 7/8"...