Question: WHat invention were created by the person who wrote the 1757 Poor Richard's Almanac?
Answer(s):
answer: Lightning rod
answer: Bifocals
answer: Glass harmonica
answer: Franklin stove

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ?c)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
?c ns:book.author.book_editions_published ns:m.040v_yc . 
?c ns:law.inventor.inventions ?x .
}