How have courts and the citizenry at large dealt with a new concept: the use of public highways by self-propelled vehicles?

It is relatively but a few years since courts and, of course, the citizenry at large who brought the cases to court were struggling with a new concept: the use of public highways by self-propelled vehicles. Illustrative of the difficulties encountered then is Nason v. West (1900), 31 Misc. 583, 65 N.Y.S. 651, 652-653, an action for damages which resulted when plaintiffs' horse was frightened by defendant's carefully driven motor carriage. The court said: 'It will not do to say that it is proper to run any kind of a contrivance upon the street, in which persons may be carried. A machine that [38 Cal.2d 847] would go puffing and snorting through the streets, trailing clouds of steam and smoke, might be a nuisance; but this is not such a case. It cannot be said that the defendant's machine is such a departure in its construction or mode of operation from other steam motor carriages, which experience has lately shown to be entirely practicable for street use, as to make it a nuisance, although because of the present novelty of horseless carriages, horses may take fright at its approach.' Judgment for the plaintiffs was reversed.