The Diurnal/Nocturnal Holmes and Watson
Have we ever thought empirically about the division of the Canonical adventures as per the time of day? Does the case activity take place primarily in the day or in the night? Is there a pattern to the Canon? Is Holmes more or less diurnal or nocturnal than Watson; does Watson run on a similar or different internal clock to Holmes?
If we add to the equation body type (somatotype), we can think in terms of Holmes as the ectomorph and Watson as the mesomorph or possibly endomorph. What does that portend for their diurnal/nocturnal characteristics, if anything?