As to the primary site of the deposition, it usually takes place at the centre of the articular cartilage. Opinions differ as to whether the cartilage cells are foci of deposition. Garrod thought so, but Duckworth found no relationship between it and any histological elements, while others locate it in the matrix. While, as before stated, the cartilage at first retains its smoothness, later it becomes pitted in patches. Ultimately the cartilage, through atrophic changes and erosions, may disappear, the joint cavity becomes filled with a plaster-like material, and the joint structures undergo more or less disorganisation. _Pari passu_ with the central atrophy of the cartilage, hypertrophic outgrowths form at its free margin. In late stages the bones, too, undergo changes; their outer layers become more dense through proliferative osteitis, while their spongy tissue becomes rarefied, and the cells of the marrow fatty. Duckworth held that uratic deposits might occur _primarily_ in the bone without any similar implication of the related cartilage. On the other hand, Garrod dissented, claiming that when the bone was involved, it was only _secondarily_ to uratic deposition in the cartilage, of which indeed it was but an extension. In reviewing the foregoing findings, it must be admitted that morbid anatomy fails to shed light on the _essential_ cause of gout. This, at any rate, is true of the older studies with which, up to the present, we have been engaged. Still, as Berkart’s more recent researches show, our knowledge of even the _morbid anatomy_ of gout is as yet but in its infancy. _Histological_ examination of the _articular ends_ adjacent to gouty joints reveals the presence of certain _cystic_ changes in the _diaphyses_. Thereupon Berkart propounded an hypothesis, explanatory of the acute phenomena of a paroxysm of gout. His view was that these cysts in the bone, at first minute, gradually enlarge. Ultimately, through concomitant thinning of the surface bone, there comes a day when the cyst bursts into the joint, its content voided into the cavity thereof.