"The law as to ‘delivery’ of a deed is of ancient date. But it is reasonably clear … ‘Delivery’ in this connection does not mean ‘handed over’ to the other side. It means delivered in the old legal sense, namely, an act done so as to evidence an intention to be bound. Even though the deed remains in the possession of the maker, or of his solicitor, he is bound by it if he has done some act evincing an intention to be bound, as by saying: ‘I deliver this as my act and deed’"