It defines the doctor's sexuality, even though London was very christian at the time it was their secret way of telling a patient that they were gay and were looking for a man. it also told if they took it both ways or if they were just
plain straight ;)
Plague doctors often wore a beaked mask with glass eye openings to protect themselves from the miasma, or "bad air," which they believed caused disease. The glass eyes allowed them to see while maintaining a barrier against infection. Additionally, the design of the mask was intended to filter out harmful vapors, with the beak often filled with aromatic substances to mask unpleasant odors. This iconic look became synonymous with their role during the plague outbreaks.
you mean ornamental glass made in Bohemia in the late 19th Century - the glass has a striated overlay of glass filaments in a different colour
Most doctors believe half a glass to a full glass of red is ok, but every individual situation is different and i suggest you ask your individual physician
Yes all glass can be recycled. The colour of the glass is of a consideration in its ultimate reuse. Clear glass generally segregated from all coloured glass and recycled into clear glass products. Coloured glasses may be accumulated for specific colour uses. Mixed glass will be reused for "brownish" glass uses or for processing into materials such as Fiberglas insulation where colour does not matter.
colour is defined by the reflection of light off a surface. So glass can be said to have no colour as light does not reflect off of it
Glass can be made into an colour by adding the appropriate materials into it.
clear
Glass color is added during the manufacturing process by incorporating metal oxides or other colorants into the molten glass mixture. Different metal oxides create different colors in the glass, with cobalt oxide producing blue, chromium oxide creating green, and manganese oxide yielding purple, for example. The amount and type of colorant used will determine the final hue of the glass.
Cobalt
red
grey
purple