Three Mahogany Mounted Hand Cranked Coloured Astronomy Hand Cranked Rotary Magic Lantern Slides, topics of the solar system with revolving planets and their satellites revolving around the sun, slide having seven rotating geared rings, the Planets with their satellites revolving around the sun, explanation of spring and neap tides, with hand written text to bottom edge “The cause of the difference in Spring and Neap Tides'' and explanation of solar eclipses, with handwritten text to bottom edge “Eclipses of the Sun total, partial and annular and a transit of Venus across the sun’s disc, auction records show this lot was part of the Harry Bland collection auctioned at S.A.S. in 2015