124 THE NATURE-STUDY REVIEW [i, 3. may 1905 



assertion that all things being equal a class which devotes an hour 

 per week to nature-study will do better work in other subjects 

 and make more rapid progress than if they devoted their entire 

 time to these subjects. [From Ottawa Naturalist, April, 1905.] 



THE METHODS OF SHERLOCK HOLMES IN NATURE-STUDY 



BY E. A. GREENING LAMBORN 



Sir Arthur Conan Doyle's famous detective was able from an 

 examination of an old bowler hat to give an account of the 

 appearance, occupation, habits, character, and worldly circum- 

 stances of its owner. Similarly, from an inspection of his friend's 

 watch, he was enabled to discover that its former owner was a 

 man of fallen estate and character, a drunkard, spendthrift, etc., 

 a physical wreck, and a victim of chronic poverty. Many other 

 instances will occur to the reader in which Holmes was able, by 

 the exercise of his sense organs and his reasoning faculties on 

 some concrete object, to construct a whole chain of facts with 

 which that object was connected. 



In the explanation of the methods by which he arrived at these 

 results, it will be seen that the faculties upon which he depended 

 for his conclusions were : — 



1. Observation, by which he obtained the external facts con- 

 nected with the object. In the case of the hat above quoted, he 

 observed the size, shape, condition, kind of lining, newly-cut 

 grizzled hairs, smell of lime-cream, tallow stains, etc. 



2. Deduction, by which he gained new facts as inferences from 

 the ones already obtained. From the large size he deduced a 

 large brain and consequent intellectual power, from the quality 

 of the hat the well-to-do state of its purchaser, and from its 

 interior stains his physical condition, among other inferences. 



3. Memory, by which he was able to associate his newly-dis- 

 covered facts with those in his past experience. For example, 

 his memory informed him that the particular shape he had 

 observed was in fashion three years before, so fixing the time of 

 the hat's purchase. 



4. Constructive imagination, by which he was able to combine 

 his facts and build them into a homogeneous hypothesis — that 

 the person he wished to discover was Henry Baker, a man 



