In the first place I desire to express my sincere and cordial thanks to my friends Sir Edward Burne Jones and Mr. William Blake Richmond, for their courtesy in allowing me to reproduce some Of their designs, and thus to give specimens of the best work in stained glass of the nineteenth century. In the next place I must explain why the direct illustrations of my text are taken from my own work only. Considerations of convenience and of good taste determined me to take this course. I am quite convinced of a general accord between my brother artists and myself as to the main principles laid down in this treatise, but it is more than probable that we may differ on minor points; and I might find myself quoting some features in their designs in illustration of an argument of my own, with which they might not wholly agree, I might read some thing into their work which was not really in their Intention. On the other hand, there are some few matters about which we do not absolutely agree, and by employing my friends' designs in direct illustration of my principles, I might appear to be guilty of an inconsistency, unless I adopted the Objectionable alternative of calling attention to the points in question for the purpose of adverse criticism.