It cannot be too constantly borne in mind that this was one of the great forces in unceasing action in the metropolis, extending its sphere of action step by step, and stage by stage, and that as years went on, the various districts of the metropolis were, one and all, in varying degree, subject to the accompaniments and consequences of its different stages of growth. And the transition was further aggravated by the natural increase of population, and by another great force--the unceasing flow of immigrants into the metropolis, the majority in search of work, others of food given by charitable people, or of any other chance good thing or adventure that might turn up. And so, on January 1, 1856, the new local authorities of the metropolis began their great task. And about forty Medical Officers of Health began to examine into and inspect their respective districts, and to inform or advise their respective authorities. What did these men find when they got well into their work? What opinions did they form as to the fearful facts with which they were promptly brought face to face, and the great social problems with which they were confronted? And what did they and their employers, the Vestries and District Boards, do to carry out the legislation which Parliament had at last enacted? The first impression of one of them was that the possessor of the office of Medical Officer of Health[59] could never become popular, "his functions bringing him into constant collision with the apparent interests of many influential persons;"--in other words, with vested interests. Others took a less personal and wider view of their duties. Thus one of them[60] wrote:-- "We have to remodel an old system--a system on which has been for centuries engrafted by slow degrees all the undesirable elements we now wish to eradicate." Another[61] was impressed by the vast amount to be done even in his own parish:-- "From what I daily witness, I make bold to state that this Vestry has a Herculean task to perform to abate all the nuisances of Rotherhithe; nuisances which have grown uninterrupted for ages, and have become inveterate customs with many." If it was a Herculean task in one parish, and that a small one, what was the task for the whole of the metropolis? Another,[62] after a few years' experience of the working of the Act, summed up the actual position--the very kernel of the case--when he wrote:-- "The working of the Metropolis Management Act might often be characterised as a war of the community against individuals for the public good."