After many disappointments it is thought that the hopes of the students for a rapid transit between Boston and Cambridge are about to be realized. A number of electric cars have been tried, but all have been found lacking in some particular or other, but yesterday afternoon a new one, of the Hewins make, ran successfully in Cambridge. The car, with the president of the West End road, and W. L. Stevens, the patentee of the motor used, on board, left the Cambridgeport headquarters, and went up Broadway to Harvard square, ascending the steep grade on Broadway without difficulty. From Harvard Square, the car went down Kirkland street, and when put at full speed made twelve miles an hour. The trial trip was entirely satisfactory, and if a few minor obstacles, pertaining to the track can be overcome, the journey to Boston will be robbed of its present horrors.