Finally, each Vestry and District Board of Works was to make to the Metropolitan Board of Works an annual report of its proceedings, including a report from the Medical Officer of Health; and the Metropolitan Board was to make an annual report of its proceedings, and present a copy to one of Her Majesty's Secretaries of State. The third of these Acts, "The Metropolitan Building Act, 1855," amended the existing laws relating to buildings in the metropolis, and laid down an elaborate code for the regulation and supervision of all new buildings. Most of this code related to the structure--the thickness of walls, &c., &c.--and had primarily in view the security of the house from destruction by fire. Only a few sections in the Act related to the infinitely more important matter of adequate provision for the health of the inhabitants, and those dealt with it in the most niggardly way. A minimum of one hundred square feet was laid down as satisfying the requirements of open space for air and ventilation around a dwelling; a minimum of seven feet in height was held to satisfy the requirements of any room in a house. And the supervision of every building, and every work done in or upon any building, was entrusted to the "District Surveyors"--officials taken over by the Metropolitan Board from the previous body, appointed under the Building Act of 1844, which had distinguished itself by its incapacity. These Acts practically laid down the framework of the machinery of the sanitary government of London, and struck the first real blow at the roots of the insanitary condition of the metropolis. The callous indifference and inaction of generations had left not a mere Augean stable to be cleansed, but a great city over 100 square miles in extent and containing two and a half millions of people, and the new authorities, when they came into existence, had not only to meet the daily needs of a vast existing population, but to make good the neglect of centuries, and to build up a sound and effective working system of sanitary administration. The task lying before them was one of enormous proportions, for on them rested the responsibility of effecting the sanitary redemption of the millions of the metropolis--as well as the infinitely greater duty of safeguarding future generations from similar sufferings and wrongs. It was, moreover, a task of almost superhuman difficulty, for arrayed against reform and amelioration were the powerful forces of "vested rights in filth and dirt." And adding to the difficulty was the huge inert mass of ignorance, and poverty, and helplessness of masses of the people. One principle contained in these Acts was of pre-eminent consequence--namely, the responsibility of "ownership." Hitherto owners had effectually escaped all responsibility as regarded the sanitary state of their property, and had dealt with their property exactly as they pleased, and regardless of the consequences to any one but themselves.