What is the origin of the name for a moving dolly - why is it called a dolly?

According to a December, 1998 of the Word Detective:





"Tracing the origin of the wheeled sense of "dolly" starts off with a bit of a surprise. I had not, until now, realized that "Dolly" (the name), as well as "doll" and all its derivatives, started out as shortened forms of the name "Dorothy." Go figure. Apparently it dates back to England in the 16th century, when someone (possibly a child) substituted "dol" for "dor." "Dolly" quickly became a common term applied generically to lower-class women (especially prostitutes), pet animals, and, of course, to "doll" toys.





More importantly, "dolly" was also, as the Oxford English Dictionary puts it, "applied to various contrivances fancied to resemble a doll in some way." There was a wooden stirring apparatus called a "dolly" used to agitate clothes in a washtub. Mechanical "dollies" punched iron and made rivets. Small wooden forms covered with doe-skin used to polish watches were known as "dollies." And somewhere along about 1900, somebody decided that a small wheeled platform looked sufficiently like a doll (perhaps only in comparison to larger wagons and trucks) to be called a "dolly." Dollies have been with us ever since, one of their most important modern uses being to allow TV and movie cameras to be easily moved about."

What is the origin of the name for a moving dolly - why is it called a dolly?
The real name for them is "hand-truck", sometimes called a "trolley" and compared to a "dolly" which is is also a wheeled platform, usually without handles used to move medium heavy loads. Not sure where the name for that came from though.