It is left deliberately unclear how much of these narrative asides Monygham has actually spoken aloud to Mrs Gould. Clearly he has told her of the (supposed) sinking of the lighter. But his emphasis on Decoud implies that he has also shared his cynical thoughts on the desirablility of having the silver still present, as well as Charles Gould's idealistic "weakness" for sending it away. Has Mrs Gould heard and absorbed Monygham's full cynical viewpoint here? We see her weeping and trembling, and later in the chapter she will reflect that "a man haunted by a fixed idea is insane."

Along these lines, the phrase "that disaster" perhaps has multiple meanings. On the surface it refers to the sinking of the lighter, though significantly we don't know that yet. Its placement makes it seem to refer to Monygham's terrible story, which we (and maybe Mrs Gould?) have just heard. As a stretch, it could refer obliquely to Monygham's love for Mrs Gould, a "disaster" in that it is doomed to be unfulfilled. Though Monygham probably didn't voice that part, on the other hand recall the pains he took to speak to her alone. From this scene onward, Mrs Gould seems perfectly aware of Monygham's affection.

There is yet a further, allegorical level, in which "that disaster," following the single word "Decoud!", could refer forwards to Decoud's fate and the ultimate price of skepticism.