A voyage in space; a course of six lectures "adapted to a juvenile auditory" delivered at the Royal Institution at Xmas 1913 (1915)
Turner, Herbert Hall, 1861-1930 · London Society for Promoting Christian Knowledge · leaf 123
ur which is notwanted; and yet they could notin early days get rid of the colourswithout also getting rid of thebending to focus. All they coulddo was to keep the colour effects as small as possibleby making the bending also small, which means thatthe rays have to travel a long way before they… … FOCUS JOURNEYING BY TELESCOPE 103 PARALLELJAYS OF LIGHT less. Newton and Gregory and others thereforeturned aside from the making of lenses and proposedto use mirrors, which can also collect rays of light toa focus if they are hollowed out to a particular shape.You can try this for yourselves with…
Astronomy -- Juvenile literature
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
