While Mr. Lister held these appointments, circumstances occurred which were calculated to stimulate to the highest degree the effort to discover some method of dressing wounds which should obviate the dangers of putrefactive changes. About 1860 a new surgical hospital was erected as part of this infirmary, and although many of the most approved principles of hospital construction had been adopted, the building proved extremely unhealthy. Pyæmia, erysipelas, and hospital gangrene soon showed themselves, affecting on the average most severely those parts of the building nearest to the ground. For several years Mr. Lister found that in his male accident ward, which was on the ground-floor, when nearly all the beds contained patients with open sores, the diseases which result from hospital atmosphere were sure to be present in an aggravated form; whereas, when a large proportion of the cases had no external wound, these evils were greatly mitigated or entirely absent. At this period the managers were very desirous of introducing additional beds into the wards, to supply accommodation for the rapidly increasing population of Glasgow; and Mr. Lister strongly and firmly resisted such increase in his wards. Some of the wards indeed at times became subject to such severe mortality that they had to be closed for various periods. One particular visitation was so serious that it was resolved to make an investigation to discover if possible the cause of the evil, which might, one would think, have been done at an earlier period. Great was the shock of every one concerned to find that a few inches below the surface of the ground behind the two lowest male accident wards, with only the basement area, four feet wide, intervening, there was the uppermost tier of a multitude of coffins, which had been placed there at the time of the cholera epidemic of 1849. The corpses had undergone so little change in the interval that the clothes they had on at the time of their hurried burial were plainly distinguishable. The wonder was, not that these wards on the ground-floor had been unhealthy, but that they had not been absolutely pestilential. Yet at the very time when this shocking disclosure was made, Mr. Lister was able to state, in an address which he delivered to the British Medical Association at Dublin in 1867, that during the previous nine months, in which his new antiseptic plans of treatment had been in operation in his wards, not a single case of pyæmia, erysipelas, or hospital gangrene had occurred in them.