Rapid transit is fast coming to Boston, or at least to the line of communication where the crying need of it has been most sorely felt-the road from Cambridge into Boston. Residents of the university town must still jog along by horse cars three-quarters of an hour to get into the city. Various schemes of improvement have been suggested hitherto, but nothing has been effected beyond a new horse-car line in competition with the horse-car monopoly of the past thirty years. The elevated railroad project, which has received this week a large majority in the lower house of the Legislature, is a peculiar one, and is only permitted to come to the boundary line of Boston until the invention has demonstrated its practicability, after which the line may be extended to the heart of the city and thence undoubtedly to other suburbs. [Ex.