THE fourth Exhibition of Television and Photo-Electric Apparatus was opened at the Imperial College of Science, London, S.W.7, by Sir Ambrose Fleming on April 5. In the course of his remarks, Sir Ambrose said that the invention of television has gone through the usual three stages. First, when everyone thought it could not be done at all. Second, when leading experts declared that even if it could be done, it was no possible use, and third, when the wiseacres said, we knew it could be done, but it is not a commercial proposition. “It has been my good fortune to be closely and practically connected with the introduction into great Britain of three important inventions, namely, the telephone, the incandescent electric lamp and wireless telegraphy, and I have seen these three stages illustrated in them all. Television by Baird's system is now a practical achievement and capable of being of real entertain.-ment value, as those know who have seen the nightly demonstrations of it by a good receiver. Our great grievance at present is the impossible hour at which the B.B.C. broadcast it, namely, 11–11.30 p.m.”There is need for a careful scientific study of the subjects that can be ‘televised’. Television is a new art and has new principles connected with it. The substantial facts on which it is based are well known and the keen amateur is doing not a little to push it forward. This exhibition showed how much has been done in this respect, and also how much is being done by great corporations with large resources.