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2. Sherlock Holmes to Dr. Watson in Doyle , Conan , A.The Sign of the Four, ( 1890 ), Bartlett's Familiar Quotations, 15th ed. , Little Brown and Company , Boston , 1980 , pg. 689 .
3. William , Thomson, Lord Kelvin , Popular Lectures and Addresses ( 1891 – 1894 ),Bartlett's Familiar Quotations, 15th ed. , Little Brown and Company , Boston , 1980 , pg. 594 .