Bluesman- HERE'S what you do. Get a plastic coke, sprite, etc bottle-the small size- fill it with barge, etc, punch a nail hole in the top, screw on the top and cover it with a piece of clipped sheep wool. It's the applicator as well as the piece that you stick back on top when you're through. I can go through a whole bottle without thinning it, the applicator keeps most of the air out, and you throw it away when you run out.
Also, keep old and unused credit cards nearby. For big jobs squirt out the glue and use the credit card as a spreader. Chuck them out too or use a hard gum erasure after they dry- I have used the same credit card for 3 years.
pete