by Thomas Jefferson
| cogs | rounds | |||||
| 1st. wheels | 56.: | 11 is | 5. | for 1. at about 4 1/2 I. making . | 254.5I circumference | =81.9diam. |
| 2d do. | 36: | 9 | 4 | for 1 | 122.5 circumference | =39.9 |
| 3d. do. | 30: | 6 | 5. | for 1 | ||
| 100. | for 1 |
a Threshing machine to be worked by 2. men single geered..
The spur wheel about 4. f. diam. 50 cogs. the wallower on the Drum shed 6. rounds which is 8 1/3 for 1. they turn the cogwheel 15. times a minute.
15 X 8 1/3 = 125. revolutions of the Drum wheel in a minute.
2. men got out nearly 1 1/2 bush. of clean wheat in half an hour, it would have been full 1 1/2 but for waste.
it would take 4. men & a girl to work, and they would get out about 40. bushels in 12 hours, when the machine comes to work glib and smooth.
one may say on the whole that it gets out the double of what the same men could thresh. but infintely cleaner. there did not appear to be 1. grain in 100. or 150 left in the straw.
Davy & Lewis & abram have done the carpenter's work of Bagwell's house in 6. days. getting the stuff & putting it together.
the Out field granary took 24 days work to get the logs, rafters & slabs & put them up completely. it may be valued then @ 48/exclusive of floors & doors.
the threshing machine I am now erecting at Tufton is as follows:
| the horsewheel has | 128. cogs. it's wallower | 23 rounds which gives | 5.5652. turns for 1. |
| Spurwheel | 60. | 16. | 3.75 |
| bandwheel | 92. Inches diameter whirl | 22 I. | 4.1818 |
| 5.5652 x 3.75 X 4.1818= | 87.272 | turns of Drum for 1. of the horsewheel |
| the diameter | 3. | beaters, or strokes at every revolution |
| 261.816 | strokes for every turn of the horse wheel |
the diameter of the drum is 5. feet, its circumference is 15.708
the diam. of the horse circle is 28. f. its circumference 88 f. he preforms it in 29" @ 3 f. per second
the velocity then of every a beater is to that of the horse as 15.708 x 87.272:88 or as 15.5/:1 to wit 46 f. in a second.
1814 Sept. this machine gets out 170 b. a day, working as in ordinary, with 5. or 6. horses.
the treble geered machine at lego got out 66. bushels in a day, with 3. horses & 2 mules.