Powell & Lealand Models No. 1 and No. 2
The tripod base was larger in Model No. 1 (L). The coarse focus support arm was large and trapezoidal in Model No. 1, and smaller and pyramidal in Model No. 2 (R).
Model No. 1 (L) compared to Model No. 2 .
Both had long limb fine focus, articulated mirror arms, Wenham prisms for binocular vision, and many other similarities.
Golub Collection instrument 149 is a Model No. 1.
Instrument 150 is a Model No. 2.