In an early, simple hay tedder described in 1852 and manufactured in Edinburgh by the company of Mr. Slight, the two wheels, via a spur wheel and a pinion, drive a set of light wheels, the rake wheels; on these two rake wheels are mounted eight rakes, which pick up and disperse the hay.
It should be noted, how-ever, that only about 1 out of every 10 STEM workers has a high school diploma or less. Those with gradu-ate degrees in a STEM job earned more than $40 per hour, nearly $4.50 more per hour on average than those with non-STEM jobs.
The overall average income for this group is approximately $21.16 per hour. The bottom of the pay range sits near $13.31 per hour, and the top verges on $38.66. Job satisfaction for Structural Iron Workers is high.