Motion-picture plays are produced under the direction of skilled stage-managers who must be specially trained for this particular business. Their work is far from being easy, for an act in a picture-play must be exact and free from mistakes, and must take place in a very short time. For instance, an act in such a play may take less than five minutes to perform, but it must be carefully rehearsed for several weeks beforehand.
There is plenty of scope for patience and ingenuity in taking motion-picture plays. If trained children or animals are required they must be found or trained; and all the resources of trick and stop photography are called upon from time to time as the occasion requires.
Edison has always held to his idea of a combination of the phonograph and motion-picture. Some time ago he said, "I believe that in coming years, by my own work and that of Dickson, Muybridge, Marey, and others who will doubtless enter the field, grand opera can be given at the Metropolitan Opera House in New York without any material change from the original, and with artists and musicians long since dead."
This prediction has been partly fulfilled, for Edison's successful talking motion-pictures marked the beginning of the "talkies" which are flourishing to-day.
XXI
EDISON INVENTS A NEW STORAGE BATTERY
Many an invention has been made as the result of some happy thought or inspiration, but most inventions are made by men working along certain lines, who set out to accomplish a desired result. It is rarely, however, that man starts out deliberately, as Edison did, to invent an entirely new type of such an intricate device as a storage battery, with only a vague starting point.
Previous to Edison's work the only type of storage battery known was the one in which lead plates and sulphuric acid were employed. He had always realized the value of a storage battery as such, but never believed that the lead-acid type could fulfil all expectations because of its weight and incurable defects.
About the time that he closed the magnetic iron ore concentrating plant (in the beginning of the present century) Edison remarked to Mr. R. H. Beach, then of the General Electric Company: "Beach, I don't think nature would be so unkind as to withhold the secret of a good storage battery if a real earnest hunt for it is made. I'm going to hunt." And before starting he determined to avoid lead and sulphuric acid.