This is one of several designs for Launcelot and Elaine worked on in the early part of his career.  A complete window  c: 1910 exists in the Stained Glass Museum be found at Ely Cathedral and can be viewed on their web site  http://www.sgm.abelgratis.com/aboutmus.htm

Andrew Stoddart,  F.I.B.G.P. - Designs

This is a design of St George and the dragon.