This is a vintage 1920s to 1930s Mellin Baby Food Jar.  The antique aqua blue bottle is embossed "Mellin's Food Co. - Boston US - Small Size" below the neck.  An "E" is embossed on the neck and "W 11" on the bottom.  The Kingston Museum of Health Care dates an identical bottle between 1880 and 1920 but the Society for Historical Archaeology pins it between the '20s and '30s.  Mellin's was an early form of infant formula created in Germany in 1867. By the 1880s, the product was being manufactured in Boston.  This vintage screw top food jar is similar in design to a mason jar.  My father, an avid bottle digger, found this bottle in the ruins of an old homestead in Virginia more than 40 years ago.  It is in great shape, free from breaks or cracks.  Clarity and embossing are good, with light sediment deposit.  (See photos). The vintage baby food jar measures about 4.75" tall and 2.5" wide.  This is a nice decorative, cottage core piece!

For more information:
https://oldmainartifacts.wordpress.com/2012/02/14/mellins-infants-foods-doliber-goodale-co-boston/
https://mhc.andornot.com/en/permalink/artifact7905
https://sha.org/bottle/food.htm#Baby%20food