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.
Pay Scale Differences by Work Setting and State. Pipeline welder helpers who work for the medical industry make the most, according to the BLS. The average mean wage in that setting was $58,680 or $28.21 per hour in 2012.Helpers who work in waste management received pay at the low end of the scale, with an average annual mean wage of $23,770 or $11.43 per hour.he average mean wage in that setting was $58,680 or $28.21 per hour in 2012. Helpers who work in waste management received pay at the low end of the scale, with an average annual mean wage of $23,770 or $11.43 per hour.