Rocking-Churns Water-Jacket Churn: Two Small Churns Rock and Their Dashers Plunge, Wings Turn Above

"Having all things arranged as represented in Fig. 1 of the drawings, the milk or cream is put in the case (a), and warm or cold water as the case may require is put in the chamber (o) at pipe (r) the exit opening being closed with a suitable stopple. And now by turning crank (q) which will revolve the shaft (f) with its wings (g), and also operate the dashers (m) and give to the churns (i) and their wings (h) an oscillating motion"

From 20 mm hardwood make the inner case n 460 x 260 mm and 380 mm deep inside. Build the outer case round it with a 30 mm space under the bottom and along both long sides, sharing the two ends; set a spacer strip under the middle. Close the tops of the side spaces with strips, fit a short brass tube in one as the supply pipe r, and bore a hole low in the other side for a rubber stopper as the exit p. In one end cut a slot 26 mm wide from the top down to 217 mm for the crank shaft. Glue two strips 18 x 20 mm up the inside of each end, 124 mm apart, as the guides. Make the lid in two halves with a handle c on each. Fill the case and the chamber with water overnight so they swell tight, then empty them.

Cut two end plates 122 x 20 mm, 375 mm long, to stand between the guides, and bore each 12.8 mm at 230 mm and 40 mm up. Bend 12 mm stainless rod into the shaft f: two cranks of 40 mm throw, 280 mm apart and pointing the same way, each pin 30 mm long, heating each bend red with the torch; leave one end long enough to pass through the slot and bend it into the crank q, 130 mm long, with a hardwood handle. Cut shaft j from the same rod, 456 mm long.

Pin the two churns on shaft j under the cranks, mouths up, and pin a hardwood wing h, 150 x 95 x 20 mm, on j between them. Cut two stems from 8 mm stainless rod, fix each in a dasher's boss, and bend its top into an eye round its crank pin so the pin sits 110 mm above the dasher, closing it with the torch and pliers. Clamp the two wings g on the shaft f between the cranks, pointing opposite ways. Put shafts f and j through the end plates and the dashers into the churns.

Stopper the exit and pour warm or cold water into the chamber through the pipe until the cream will sit at about 15 °C. Lower the frame into its guides, pour in about 22 litres of heavy cream, checking it with the thermometer, and put the lid on. Turn the crank steadily, timing it. When the butter comes, lift the frame out, gather the butter, drain the buttermilk and the chamber, wash the butter in cold water until it runs clear, salt and weigh it.

**Samuel Gissinger** of Allegheny, Pennsylvania, US 25,502, 20 September 1859, "Churn". He claimed the arrangement in the movable frame e of the oscillating churns i with dashers m and wings h, in combination with the revolving shaft f and its wings g. The patent gives no sizes; every size here is ours. His Fig. 1 draws the two dashers at different heights, but both churns are "secured to the shaft (j)": cranks out of step would push them opposite ways and bind, so ours are in step. His case is rounded at the ends and the water chamber tapered; ours is square.