Milkmaids, Antigonish County, early 1900s. Courtesy of Antigonish Heritage Museum. Restoration: Anne Louise MacDonald     The History of Aprons on Facebook, which includes this photo, would also explain about milkmaids wearing aprons.   https://www.facebook.com/photo.php?fbid=10152109083201188&set=a.106537651187.98622.575201187&type=1