Since the letter and remarks respecting Steamboat Inspectors were published in No. 47, Charles W. Copeland, the Chief Inspector of this district (not Robert L. Stevens,) presented us with the new act relating to steamboats, printed at Washington. Section 42 of it excepts ferry boats, tug boats, and towing boats, and all steamers under 150 tons burden—these do not come under the provisions of the act. The Inspectors he informs us have done all they possibly could to carry out the law promptly and efficiently, but have been much troubled because other governmet officers have not done their duty in furnishing them with proper instruments.— We have received a communication on th.s subject, which we will publish next week.