I pulled this huge jar out about 5 months ago and I was surprised that I got it whole. And since then, I have found little info on the bottle. Here's a pic of the jar itself.
Sorry for the poor pics...it has some thin embossing.
A.G. Smalley & Co. were very successful producers of a number of bottles, particularly for fruit and whiskey. Your Royal fruit jar is one of their most commonly found jars. Since it has a ground lip, I would date it from 1896-1910. It is a nice jar that I would be happy to dig myself, but in mint condition usually sells for $5-10.
Keep up the digging, the jar is a sign you're in a good spot!