Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. The original program of tests that was planned by the Pennsylvania Railroad Company to be made on the Locomotive Testing Plant at St. Louis, in 1904, included tests of one Of the Company's simple passenger locomotives of the Atlantic type with D valves* and a locomotive of this type was prepared and held in readiness for the tests, but as the time at St. Louis was not sufficient, these tests could not be carried out.