The presence of the bullet in the knee-joint was later determined by the X-rays, and Mr. Bowlby removed it successfully. Seven months later the range of movement was nearly normal. I may add that I saw several instances of large leaden bullets lodging in the popliteal space, and a comparatively insignificant number of bullets of small calibre in the same situation. This was very striking, in view of the immense relative frequency of use of the latter forms. There is no doubt, moreover, that small bullets rarely lodge even in the neighbourhood of joints, unless at the distal end of a long track. To take the extreme example of large bullets, those employed as shrapnel, in comparison with the frequency with which wounds were produced by them, bullets lying at the bottom of short tracks in the neighbourhood of joints were not uncommon. Thus I saw one lying over the hip-joint, and another in close proximity to the shoulder capsule. Wounds of the third class, where the bones had been superficially grooved, were in some respects the most serious. This was especially so in the knee and ankle joints, and some cases will be quoted later under the heading of the special joints to illustrate this point. Danger only arose in the event of suppuration; and here the presence of the long oblique superficial track in a neighbourhood liable to comparatively free movement was the important element. Such tracks usually opened the synovial sac more extensively than direct perforating wounds, and if suppuration occurred in any portion of the track, the pus was very liable to be sucked into the joint on any free movement. The presence of fine splinters of the bone displaced in the production of the groove was also a special character of wounds of this class. Another point worthy of mention is that in these cases it was not always easy to be quite certain whether the joint cavity had been implicated or not, since cases often occurred in which, although the bones had been grooved, the joint cavity escaped. The indication, however, was to consider any wound in the immediate proximity of a joint as perforating until it was healed. This course was the more easy to take, since a large proportion of such wounds were accompanied by some degree of synovial effusion, even when the neighbouring joint had escaped puncture.