A description of the laboratory building would be incomplete without mention of room Number 12. This is one of Edison's favorite rooms, where he may frequently be found seated at a plain table in the center of the room deeply intent on one of his numerous problems. It is a plain little room, but seems to exercise a nameless fascination for him.
Passing out of the building, we come to the four smaller buildings, which are known as Numbers One, Two, Three, and Four. The building Number One is called the galvanometer room. Edison originally planned that this should be used for the most delicate and minute electrical measurements. He went to great expense in fitting it up and in providing a large number of costly instruments, but the coming of the trolley near by a few years afterward rendered the room utterly useless for this purpose. It is now used as an experimental room, chiefly for motion-picture experiments.
Building Number Two is quite an important one. As the visitor arrives at the door he is quite conscious that it is a chemical-room. Here a corps of chemists is constantly kept busy in carrying out the various experiments Mr. Edison has given them to perform. This room is also one of his special haunts. He may be seen here very frequently experimenting in person, or seated at a plain little table figuring out some new combination that he has in mind.
A chemical store-room and a pattern-maker's shop occupy building Number Three, while Number Four, which was formerly used for ore concentrating experiments, is now used as a general stock-room.
We have only attempted to afford the reader a passing glance of this interesting laboratory, which for many years has been the headquarters of Edison and the central source of inspiration for the great industries he has established at Orange. Around it are grouped a number of immense concrete buildings in which the manufacture of phonographs, motion-pictures, and storage batteries is carried on, giving employment to as many as four thousand people during busy times.
Needless to say, the laboratory has many visitors. Celebrities of all kinds and distinguished foreigners are numerous, coming from all parts of the world to see the great inventor and the scene of his activities.