Where was the original Lassie from?

All Lassie dogs used in the movies and television shows were of the Collie Breed. obviously different dogs were trained for differfent types of stunts. at times the use of synchronized projectors- an early form of trick Photography,, left something to be desired and one could tell the crisis- say a brush fire, was phony and the dog was never in any real danger. again, obviously different dogs were used over the long lifetime of the show, and for different types of stunts. One canine size did not fit all situations! a very interesting sidelight is the program was chemically pure of the slightest traces of comedy- heavy drama indeed- but no comic relief. This was practically unknown among juvenile programming, with the possible exception of religious dramas.