Top ten books on Gutenberg

#1 The Outline of Science, Vol. 1 (of 4) by J. Arthur Thomson (21431)
#2 Manners, Customs, and Dress During the Middle Ages and During the Renaissance Period by P. L. Jacob (16654)
#3 Illustrated History of Furniture by Frederick Litchfield (11252)
#4 The Kama Sutra of Vatsyayana by Vatsyayana (10522)
#5 Pride and Prejudice by Jane Austen (9269)
#6 Searchlights on Health by B. G. Jefferis and J. L. Nichols (9007)
#7 History of the United States by Charles A. Beard and Mary Ritter Beard (8348)
#8 Our Day by William Ambrose Spicer (8004)
#9 The Adventures of Huckleberry Finn by Mark Twain (7354)
#10 The People's Common Sense Medical Adviser in Plain English by Ray Vaughn Pierce (6712)

I stumbled across this while searching for some other texts. Only #4, #5 and #9 are the well-known ones. It seems rather bizarre that people are downloading the History of Furniture, the Dress from the Middle Ages more often than the Kamasutra or Pride and Prejudice (No need for a gender-based query, we all know!). Good to know that Science is trumping them all, or is the web full of only dweebs?

I am really perplexed. Any ideas?