When large steamships appeared in the late 19th century with telemotors hydraulically connecting the wheel on the bridge to the steering gear at the stern, the practice continued.[3][4] However the helmsman was now no longer directly controlling the tiller, and the ship’s wheel was simply turned in the desired direction (turn the wheel to port and the ship will go to port). Tiller Orders remained however: although many maritime nations had abandoned the convention by the end of the 19th century, Britain retained it until 1933[5] and the U.S. merchant marine until 1935.[3] One of the reasons for this system continuing, apart from it being a long-established maritime tradition, was that it provided consistency—regardless of whether a vessel was steered directly by the tiller or remotely by a wheel every vessel had a tiller of some sort and so a tiller order remained true for any vessel. During the transition period the wording of the order was changed, to specify “Wheel to starboard” or “Wheel to port”.[6]

Although this system seems confusing and contradictory today, to generations of sailors trained on sailing vessels with tiller steering it seemed perfectly logical and was understood by all seafarers. Only when new generations of sailors trained on ships with wheel-and-tiller steering came into the industry was the system replaced.

http://www.facebook.com/profile.php?id=1239538257

http://www.truthorfiction.com/rumors/b/brassmonkeys.htm
http://en.wikipedia.org/wiki/Brass_monkey_(colloquial_expression)

It appears to have had its origins in the twentieth century, having more to do with brass casts of the famous 3 Wise Monkeys from China and Japan, than with the navy.