I understand that Scotland Yard is not losing an unnecessary minute, but there are obvious difficulties in the way of decisive action.

It is considered worse than useless to effect isolated arrests, as these tend only to put the other members of the gang on their guard.

The chief inspector tells me that he had some hope of being able to make a big haul tonight.

The principal drawback is the language bar.

Chinese interpreters are few and far between in London, and those who do exist--in the East End, for instance--have long since lost any useful acquaintance with events in their own country.