Joseph McKenna

“ Before the time of either patent the world knew that heat disintegrated some things and melted others, and we cannot concede invention to the thought that that might be true of different kinds of asphalt. Indeed, even in the face of the grave testimony contained in this record given by unquestionably expert men, we find it also difficult to concede that it was an exertion of invention to apply heat to the edges of an excavation to make a bond between the old and the new material. ”

“ In other words, the mixing of the old and new material around the edges of the excavation, and 'adding of new material in direct contact with the old material, smoothing and burnishing it,' is the essence of the invention; and so unqualifiedly is this true that a witness of petitioner testified that if the heat which was applied not only melted, but burned, the immediate surface and as well 'the particles deep down,' and the material thus burned raked away clean before new material was applied, the method of the patent would be followed. ”

“ In practising my invention, however, I subject the spot to be repaired and the surrounding edges to such a degree of heat that the surface asphalt-not only the exact spot to be repaired, but the surrounding portion, to a greater or less degree-is reduced to the soft pliable state in which it is originally laid. With a rake or other suitable instrument it is then agitated and mixed with enough new material to fill up the spot to be repaired. ”