In time of war, the ambulance chassis is, roughly speaking, anything big enough and sufficiently reliable that can be made available. For example, motor omnibuses can be without much difficulty adapted to this class of work, while touring cars are often quite suitable. The qualifications in the latter instance are fairly ample engine power, thorough reliability and strength for working over rough road surfaces, very strong springs and ample wheelbase, so that the ambulance body shall not overhang the rear of the chassis to too great an extent. To form the complete vehicle, what is wanted at such times is not necessarily a luxuriously-equipped conveyance, but is rather a quite light and simple body sensibly constructed to bear its load, and capable of standing any amount of jolting without either its component parts shaking loose among themselves, or the body as a whole becoming insecure in its connections with the chassis. As regards the interior equipments, in most instances all that is needed is provision for readily fixing in place two or four stretchers as the case may be, and also for loading the stretchers on to and unloading them off the body without difficulty, and without unnecessary discomfort to the patient. The standard types of ambulance body approved by the British Red Cross Society consist of simple but stout wooden frameworks with all the joints reinforced by angle irons held by bolts through the wooden members, and not merely by wood screws, which are liable to work loose. Over this framework is stretched a cover of waterproof canvas that has been treated with rubber, while the front and back of the vehicles are covered in by waterproof curtains of similar material, capable of being drawn aside or raised quite easily so as to enable attendants, with the minimum of difficulty, to lift the loaded stretchers into the vehicles. Medical experts who have experience in the carriage of wounded men do not appear to be entirely in agreement as to whether the stretchers in a motor ambulance should be rigidly secured to the vehicle body, or should be carried by some form of springing supplementary to that of the car itself. In some examples of ambulances in regular use in this country, additional springing is provided by suspending the body from the chassis by means of semi-elliptical or complete elliptical springs. In many others, no springing other than that of the vehicle itself is interposed between the stretcher and the ground. One point at least on which there is universal agreement is that on no account must any rolling motion of the stretcher relative to the vehicle body be permitted, as motion of this kind causes acute discomfort to the patient, and often leads to physical effects similar to those occasioned by the rolling of a vessel at sea.