Mid-Century Hanging Lamp, Finnish Tupa

Mid Century hanging lamp, glass, metal, wood, probably teak, in excellent condition, pull down works fine, except the light has burned out after 40 years. The question seems obvious but the solution has eluded me. What is the manufactures instruction to replace the light bulbs? So I seek the manufacture and designer. Please, share with us if you know. Is the designer or manufacturer from Finland? If so, there might be a logical way to replace the bulb. Maybe from the wooden side instead of the top or bottom. 

Please share the name of designer and manufacture? Please, I need more light. My images seem dark.