Besides controlling the experiments of feeding and inhalation, the inoculation experiments play a still more important part, as they furnish the correlation, necessarily, of the histological changes found as the result of poisoning by means of lead. In all the animals which have died of poisoning, certain definite trains of symptoms made their appearance. These symptoms were in practically all particulars similar to those observed in industrial lead poisoning in man, the onset of the affection and its clinical course corresponding to the symptom-complex in man, including those of cortical involvement, and often similar to the classical Jacksonian variety. Throughout these experiments the animals exhibited no signs of irritation, and during the initial period, even, when loss of weight was a noticeable feature, their appetites remained exceedingly good; they were quite friendly, and purred loudly when stroked; but when symptoms of poisoning became manifest, particularly the onset of paralysis, a definite change in mental phenomena took place: the animals became quarrelsome, highly apprehensive of danger without cause, morose and lethargic by turns. At this stage, in more than one instance, acute encephalopathy supervened. The mental change was peculiarly striking in reference to Mott’s case, quoted on p. 71, as in all respects it was exactly analogous with the train of symptoms recorded in that case. To sum up, the symptoms produced in the experimental animals by the lead compounds inoculated and respired, no matter what the particular compound of lead experimented was, were as follows: 1. Slight preliminary rise in weight at the commencement of the experiment, lasting from one to two weeks. 2. Progressive loss of weight, mainly due to the disappearance of all fat, subcutaneous, kidney, mesenteric, etc., with associated anæmia, and the curious sunken and pinched faces commonly associated with saturnine cachexia. 3. Paresis of various types. In the cat the muscles first affected are those of the back and the quadriceps extensor of the hind-limbs. The onset of the paralysis is slow and insidious, but may be acute; as a rule weakness in the muscles of the lumbar region and the spine are the first symptoms; secondly, inability to jump, owing to the weakness of the quadriceps extensor, while the animal tends to fall over when turning round quickly. Encephalitis occurs, and is frequently fatal. As a rule the affection is unilateral; complete loss of consciousness may occur, followed by slow but complete recovery. The animals gave no evidence of suffering pain, and, when recovered from an attack of encephalopathy, would at once take milk, but seemed dazed and uncertain in their movements. When the animals reached the stage of paralysis, they were destroyed under anæsthetics, and subjected to post-mortem examination. The post-mortem findings of a typical case were as follows: