With the increase in through passenger service we note the appearance of the vestibule, protecting the communication between cars. Originally this vestibule was narrow, about the width of the car door, and was introduced about 1882, although experimented with as far back as 1845. The equipment of the "Exposition Flyer," operated from New York to Chicago during the World's Fair, was the first, we believe, to appear with full-width vestibules, these being originally designed as offering less atmospheric resistance to high-speed trains, but having subsequently been found a more economical, attractive and safer form of construction. The question of steel cars and composite steel and wooden cars is having very careful investigation and experiment at the present time. While considerably used, the results of the use of these cars must be awaited. After the factor of safety has been determined the question of tare weight per passenger carried will naturally arise. In this country our weights are now far in excess of all foreign railroad practice. This enters into the resistance and cost to produce the service. CAR HEATING. The original method of heating passenger cars by direct radiation from coal or wood stoves was a source of discomfort to the passengers as well as a menace in case of disaster. This brought about in the late '80s the introduction of the "Baker Hot-Water Heater," which was a great improvement for the comfort of passengers, but still left a fire in the car. In many instances of collisions and derailments during this period, especially in winter, the cars were set on fire and the wreckage consumed from the fire scattered from the stoves or heaters. Experimentally, steam from the locomotives was used, but the difficulties in securing satisfactory couplings between the cars, the drain on the boiler, and the fact that the locomotive was sometimes detached from the train, were obstacles. One of the Western roads even attached a separate car for the sole purpose of supplying heat and light. The growth in the capacity of locomotive boilers, and the perfection of the couplings between cars, have led to the present practice of car heating, which entirely eliminates the presence of any fire or source of danger from that source. CAR LIGHTING.