John Chinaman is a natural born gambler, and to obtain admission to one of his resorts is a more difficult matter than it would be for an ordinary man to obtain an audience with the Queen of England.

He does his gambling behind walls of steel plate and behind doors that, banged shut as they are at the slightest sign of danger, would have to be battered down with sledges or blown open with dynamite before one could gain admission, and by that time the inmates would have all escaped and nothing would be left behind to show the nature of the business carried on.
Crime runs rampant in this section of the town, and when a Chinaman is murdered, in nine cases out of ten the slayer escapes punishment at the hands of the law, though he may have it meted out to him in some horrible form at the hands of the dead man's friends and relatives.
To go through the Chinese quarters by daylight is a sight well worth seeing, but to go through there with a guide after the night's dark shadows have fallen, is more than that.

It is a revelation.

These guides are licensed by the city, and are under the protection of the police.
They are as well known to the Chinamen as they are to the officers of the law, and the visitor is always safe in following wherever they may lead.
The tenement houses in the poorer sections of any great city are a disgrace to modern civilization, but a Chinese tenement house is as much worse than any of these as can be imagined.

In one section of the Chinese quarter at San Francisco is a four-story building above ground, with a double basement below, one being under the other, and with an open court extending from the lower basement clear to the roof.