A correspondent of the " Tribune " states that the operators of the telegraph running between Buffalo and Milwaukee, working under Morse's patent, have for some time past discontinued the practice of recording the signs, and have instead thereof received their messages by sound. This they have done for the last two years, without interruption, having found that they could receive three messages by sound in the same time which would be occupied in receiving two under the other system ; and moreover, that in receiving by sound they make fewer mistakes than they ware liable to in the use of the dots and dashes, arid can also dispense with half the number of operators. The mode of receiving messages by sound is very simple, and one operator is sufficient instead of two, who are required when the signs are recorded. The operator sits by the table in any part of the room where the message is received, and writes it down as the sounds are produced. The different sounds are made by the striking ot the pen lever upon a piece of brass; thus three raps in rapid succession are made for the letter A, two raps, an interval, and then two raps more, are made for B, and so forth. We cannot see how fewer operators are required, or less mistakes made by sounds than by marks, and we question the correctness of the statement. Our object, however, in alluding to this subject at this time, is to point out the real genuine principle of Morse's invention. It consists in employing an electromagnet, to make marks, or by its vibrations in any manner to convey the messages. It makes no matter whether it conveys those Messages by sounds or by marks, in any telegraph which uses an electro-magnet operated by breaking and closing the circuit, the electro-magnet proclaiming the message by raps as spoken of above, or by making marks, embraces Morse's principle. According to Judge Kane's decision, the recording of the mes'sages was the new art embraced in Morse's patent. The recording and the sounding of messages are only the effects produced by Morse's invention, not the invention itself, We give the IBarieiiile-ciEjiifiJiLsuaiifoft ittiujgjuaaniag. as explained by Prof. Morse himself, in Alfred" Vail's work, entitled "The American Telegraph."