Opinion by
Mr. Chief Justice Brown,The Cochranton Telephone Company and the Merchants & Farmers Telephone Company presented their petition to the Public Service Commission for permission to consolidate. This permission was granted, and an appeal to the Superior Court followed. That court affirmed the action of the commission: Shaffer v. Public Service Commission, 74 Pa. Superior Ct. 597. This ap*458peal from the order of the Superior Court is by an intervening stockholder of the Cochranton Telephone Company, and the only question raised is the constitutionality of the Act of July 22, 1919, P. L. 1123, under which the Public Service Commission approved the merger.
In the report of the commission approving the merger and in the opinion of the Superior Court affirming the commission’s action there are references to testimony showing substantial differences between telegraph and telephone companies; but, without regard to this, there is a plain controlling reason why the Act of 1919 cannot be regarded as violative of article XYI, section 12, of the Constitution, prohibiting the consolidation of telegraph companies. An act of assembly is void only when it “clearly, palpably and plainly” violates the Constitution : Sharpless et al. v. Mayor of Phila., 21 Pa. 147; Com. v. Puder, 261 Pa. 129; and a doubt as to the constitutionality of an act of assembly is to be resolved in favor of the validity of the legislation: Com. ex rel. Wolfe v. Butler, 99 Pa. 535; Com. v. Grossman, 248 Pa. 11. Applying these touchstones to the statute under consideration, and remembering that at the time our present Constitution was adopted, the telephone, though perhaps appearing in the dreams of inventive genius, was utterly unknown, not only to the public, but to the intelligent framers of the Constitution as well, not even a doubt can arise as to the constitutionality of the Act of 1919. That of which nothing was known forty-seven years ago could not then have been in the minds of the members of the constitutional convention when they submitted their work to the people for approval; and what is not there forbidden the legislature may do. This is all that need be said in support of the validity of the legislation under consideration, and the order of the Superior Court is affirmed, upon condition that the Cochranton Telephone Company proceed forthwith to surrender all of its charter rights as a telegraph company. Upon the filing of a proper certificate with the prothono*459tary of the eastern district, showing such surrender, this appeal will be marked dismissed, at the costs of the appellant.