Resource

The vital part of an electric lamp is the filament. No matter how carefully the lamp is made in all other respects everything depends on the filament - the light - the economy, the durability and the life.
If the filament is made of carbon, then the light is poor and the current cost high. If it is a”pressed" metal filament in short brittle pieces though the light may be bright and economical, the lamp is fragile.
But if its a Mazda British Made drawn wiire filament in one continuous length then the lamp possesses all the qualities which make a perfect lamp - brilliant light, low current cost, great mechanical strength and excellent  long life. MAZDA lamps are obtainable from Reavell Bros, Ironmongers, Alnwick