She could then go home, make up for her part; draw out a plan of action, with the help, perhaps, of Mr.Weiss, provide herself with the necessary means and appliances and, at the appointed time, call and collect you." "That is assuming a good deal," I objected.

"It is assuming, for instance, that she lives within a moderate distance of Sloane Square.
Otherwise it would have been impossible." "Exactly.

That is why I assume it.

You don't suppose that she goes about habitually with lumps of prepared sugar in her pocket.

And if not, then she must have got that lump from somewhere.