Invaders from the Infinite. by John W. Campbell

In the year 2129, a doglike alien race asks the scientists Arcot, Wade and, Morey to assist them with defending their solar system from an enemy force. Their journey takes them to other solar systems across the galaxy as they build battle spacecraft out of pure matter using only their minds. Invaders from the Infinite is the third and final installment in the Arcot, Morey, and Wade trilogy. It was originally published in April 1932 in Amazing Stories.