nearly nine o’clock
Then I should be very glad to compare impressions as to this most interesting problem which has been submitted to us this morning . '' I knew that seclusion and solitude were very necessary for my friend in those hours of intense mental concentration during which he weighed every particle of evidence , constructed alternative theories , balanced one against the other , and made up his mind as to which points were essential and which immaterial . I therefore spent the day at my club and did not return to Baker Street until evening . It was nearly nine o'clock when I found myself in the sitting-room once more . My first impression as I opened the door was that a fire had broken out , for the room was so filled with smoke that the light of the lamp upon the table was blurred by it . As I entered , however , my fears were set at rest , for it was the acrid fumes of strong coarse tobacco which took me by the throat and set me coughing . Through the haze I had a vague vision of Holmes in his dressing-gown coiled up in an armchair with his black clay pipe between his lips .