John Archibald Campbell

“ To escape the incessant and intense competition which exists in every department of industry, it is not strange that persons should seek the cover of the patent act, for any happy effort of contrivance or construction; nor that patents should be very frequently employed to obstruct invention, and to deter from legitimate operations of skill and ingenuity. Thid danger was foreseen, and provided for, in the patent act. The patentee is obliged, by law, to describe his invention, in such full, clear, and exact terms, that from the description, the invention may be constructed and used. ”

“ It is agreed that a circle contains a greater area than any figure of the same perimeter; that the conical form is best suited to resist pressure from within, and that the reduced size at the bottom of the car is favorable to its strength. The introduction of the cars of the plaintiff, upon the railroad, for the transportation of coal, was attended by a great increase of the loads in proportion to the weight of the car. ”

“ It is also true that the properties of the circle, and of circular forms alluded to in the patent of the plaintiff, are understood, and appreciated, and have been applied in every department of mechanic art. One cannot doubt that a requisition from the transportation companies for cars of a diminished weight, and an increased capacity, upon the machinists and engineers connected with the business, would have been answered promptly by a suggestion of a change in the form of the car. ”