Try the link below instead as your link doesn't work. First, if it is a gallon size (rather than a quart) it cannot be used for canning anything anyway. They are used just for dry storage.

There are no provisions or guidelines or processing times for anything larger than quart jars.

Second, if they are actually quart sized they aren't recommended for use in canning any longer, primarily because of the high rate of seal failures with them. Rather they are considered vintage/antique collectibles and used for decorative and dry storage purposes. They are sized so that modern canning lids will not fit them.

Dave

Here is a link that might be useful: Vintage Jewel Jar