_I was reading through A History of Japan: From stone age to superpower by Kenneth G. Henshall and I came across an interesting term I had never heard of before. This term was he-gassen (屁合戦), or 'farting competition'. This, of course, spurred my interest and I quickly made a google search for the term. The search revealed a digitized scroll hosted at the database for Japanese and Chinese classics at Waseda University Library. (Which is, by the way, an excellent source for finding primary sources) The picture below is from said scroll, and you can also peruse the scroll in its entirety here.
Picture
Apparently, similar drawings were used to ridicule westerners towards the end of the Edo period, with images depicting the westerners blown away by Japanese farts. (Henshall 2004:70)


Sources:

Hegassen emaki. Date and publisher unknown
Henshall, Kenneth G. A history of Japan: From Stone Age to Superpower. New York: Palgrave Macmillan, 2004.