anarchy: absence of rule, disorder.
Gordon Riots: in 1780, led by the fanatic Lord George Gordon. The mob raised the cry of 'No Popery' on account of a law then proposing to remove hardships from Roman Catholics. Riot and plunder were the real object of the mob. The disorder had to be suppressed by military force.
Police: organised in 1829 by Sir Robert Peel, after whom the members of the force were called 'bobbies' and 'peelers.'
[60. THE GOVERNMENT OF THE CITY. PART I.]
Denominations: religious bodies or sects, the members of which are all called by the same name. (Latin nomen, a name.)
every conceivable topic: every subject you can think of.
community: a people, the public.
achieved: won by effort.