The Nature And Cause Of Bloom And Dimming On Lamp Blown Glassware

A summary is given of work on the causes of "bloom" or "dim" on table-worked glassware, together with a detailed report of the work carried out in the laboratory. The conclusion arrived at is that the cause of the dimming is the presence of sulphur compounds in the gas. The nature of the reactions are discussed, and photomicrographs are given, showing the character of the dimmed surface. The effect of glass composition on tendency to dim has been studied, and attempts have been made to devise a means of purifying town' gas to render it sufficiently free from sulphur for lamp-working purposes.