Subject: ACG C-3 supplementary lenses
                                    From: (Phillip Sterritt)
                                    
                                    'The Argus 35mm Guide and Reference Book' by Dr.  Kenneth Tydings,
                                    S.P.E., indicates that 'auxiliary compound lenses', both telephoto
                                    and wideangle , were available for the C-3.  Both of these screw onto
                                    the front of the 50 mm lens.  There was a 'coordinated viewfinder' for
                                    the wideangle and a 'coordinated viewfinder mask' for the telephoto.
                                    There's a pretty small picture of each lens;  no focal lengths (or
                                    equivalents) are provided, but it states that the wideangle provided a
                                    'moderate' increase in angle of view and the telephoto gave a 'not
                                    very material increase in image size' (try to contain your enthusiasm,
                                    Doctor!).  Both of these apparently pre-dated the Sandmars, as there
                                    is an addendum describing the 'recently available' Sandmars.  I
                                    actually have two copies of that book;  one is the original version
                                    and the other is the 'seventh printing'.  The original only mentions
                                    the Tele Sandmar, the other shows the wideangle Sandmar as well.  I
                                    figure this means the Tele Sandmar predated the wideangle.