ME. BULLOCK'S "D" STAND. 67 



obliquity obtained with the Centennial stage, is greater 

 than that obtainable in Mr. Bulloch's stand. 



The principal points are thus presented ; it remains 

 for the reader to use his own election. Either of the 

 two stands will bear comparison with any foreign stand 

 extant. 



Mr. Bulloch also supplies another stand, which he 

 calls his 



SMALL BEST STAND " A-B." 



This instrument is similar in construction to the 

 large stand, but smaller, excepting the body tube, 

 which is of the standard length in all his instruments. 



MR. BULLOCH'S "D" STAND. 



This has been selected by the author for description 

 principally because it is a medium-sized " student's 

 stand," and furnished with a concentric adjustable stage, 

 it being desirable to present as much variety as possible 

 within our circumscribed limits. 



The adjustable concentric stage can be centred to any 

 objective ; the edge of stage is bevelled and graduated, 

 so that angles of crystals can be measured ; it has a 

 complete revolution. Its glass stage is perforated in 

 the centre, has brass fittings, so that the "Maltwood 

 Finder " can be used ; and its motion is perfectly smooth 

 under the highest power. To the underside of stage is 

 fitted a tube for accessories; this can be removed so 

 that the utmost angle of oblique light can be obtained. 

 Plane and concave mirrors and lateral motion for ob- 



