Appeal from a decision of the Commissioner of Patents, refusing six claims for a patent on a machine for mining coal; the ground of the decision being that no patentable advance has been made over the prior art. We have carefully considered the points made in appellant’s brief, as elucidated by his argument at the hearing of the case, and, being convinced that the decision of the Patent Office tribunals was right, we affirm it upon the grounds stated by them. Affirmed.