FEDERAL OFFICIAL STREET GUIDE And Pocket Directory of Detroit. Shows Both Old and New Corner House Numbers on Any Street or Avenue, Paved Streets, New Car Lines, Steam and Electric Railways, Also New Map of the City Lithographed In Five Colors. 1920-21 ed.The City of Detroit renumbered all its street addresses back in 1920 (and renamed a few streets too!) and as a result genealogists often need to know both the "old" and the "new" addresses to follow families in the census records and city directories. While this little pocket directory doesn't give individual addresses for every house and business, it does give the old and new numbers for corner houses. And often just knowing which block to look for is enough to find a census record or directory entry. :-)
It's a good day!