Here is a vintage roll over (a/k/a bottoms up, tipping) style jigger marked “Webster Sterling 8515”. Webster Co. started in North Attleboro, MA in 1894 and became a subsidiary of Reed & Barton in 1950. They are still in business today. I am estimating this is circa 1950 but it could possibly be several / many years either side of that I would guess.
It measures approximately 5 inches across including handles. The top diameter of the cup is 1 and 1/8 inches. It holds 1 and 1/2 ounces. It weighs 21.7 grams.
I believe the earliest patent for this roll over type jigger was Patent No. 115831 for ” Measuring Container”, dated July 25, 1939, obtained by H. B. Kaempf. This type jigger was offered and advertised as “Host” and “Hostess” jiggers with the “Hostess” jigger holding 1 ounce (offered in silverplate) and the “Host” holding 1 and 1/2 ounces ( offered in either sterling or silverplate). I don’t know who actually manufactured these “Host” / “Hostess” jiggers. Just wanted to provide a little history!
This jigger is available for sale here at my Etsy shop: https://www.etsy.com/listing/629046879/webster-sterling-silver-roll-over-jigger