In the 1950s- and 1960s, more sports coaches began to use rowing machines for training and assessment of athletes' performance. One such rower developed at this time was the Harrison-Cotton machine, the brainchild of John Harrison of Leichhardt Rowing Club in Sydney and Professor Frank Cotton, produced by Ted Curtain Engineering. This was the very first piece of equipment able to measure athletic power with great accuracy, and it also imitated the actual experience of rowing more closely than any previous rowing machine.
The rowing machine itself is unlike any other on the market with its patented water filled flywheel. It is hard to exactly copy the action of a scull on the water, but the mechanics of the flywheel spinning in water comes in a close second on dry land. The fact that the water is 800 times denser than air means that there is no need for any extra resistance or dampening that you will find in normal air rowers. The faster you pull, the more resistance is generated giving it infinite variability. However, if you want to be able to practice rowing with a faster stroke, you will have to reduce the amount of water in the tank unlike an air rower where you just have to adjust the baffle.