Sherrill was sure that picnic was an English word for an English custom, he ridiculed his French visitors for not spelling the word correctly. “That pleasant word “picnic,” so popular at all times in our country, “he writes, “played havoc with the spelling powers of the French. Their ways of rendering it were various, of which let “pique-nique” be a sample. Their appreciation, however, of that rustic entertainment was as enthusiastic as their spelling of it was uncertain.”
See Charles Sherrill French Memories of Eighteenth-Century America. New York: Scribner & Sons, 1915
See Charles Sherrill French Memories of Eighteenth-Century America (New York: Scribner & Sons, 1915); https://www.nyhistory.org/blogs/charles-h-sherrill-hitler-and-the-1936-olympiic.