There is, therefore, no other course open to us but to assume the infectiousness of the disease, and thus the spread of leprosy is readily understood; while by the assumption of heredity, or Baumgarten’s latent germinative infection, it remains absolutely inexplicable. These two last causes are to our thinking absolutely proved to be non-existent by the case of Father Damien; by the results of our investigations in North America; and by the diminution of the disease in the descendants of lepers in the Norwegian towns. But _direct proofs_ of its contagiousness may also be obtained. Such are given by Drognat-Landré in his book, and also by many other observers. Norway can supply many proofs; but against these it can always be urged that it is impossible to exclude the possibility of inheritance on account of the widespread nature of the disease. But we think we can supply from Norway a still better proof in the shape of the gradual diminution of the disease during the last thirty-five to forty years. Up to 1856 leprosy probably increased in Norway; we cannot speak more definitely, as previous to that year there was no exact or sufficient enumeration of the lepers. But we have grounds for believing that we have obtained, by means of the yearly census begun in 1856, a pretty exact knowledge of the number of new cases in the years 1851-55, and this shows that the number is considerable, and almost exactly corresponds with the number of new cases in the next five years, 1856-60. This, we think, indicates that the total number of lepers in the two quinquenniums was pretty much the same. Now we know that there were in Norway in 1856 over 2800 lepers. The number was estimated in 1836 at 659, and in 1845 at 1122. According to this estimate a considerable increase had taken place. We can, however, with certainty say that the numbers for 1836 and 1845 are too low. In the first place, the enumeration was not undertaken by medical men, and secondly, even now, there are many lepers overlooked at every enumeration, or, to speak more correctly, they are not discovered because the patients conceal their condition. But that the number of those overlooked in the years 1836 and 1845 can have been so great as the difference between the numbers for those years and that for 1856 is scarcely credible, and it therefore appears probable that the number of lepers in Norway increased during the first half of the century. In the year 1856 the first Leper Asylum was opened in Bergen. Previously to this we had in Bergen the St. Georg and Lungegaard’s Hospitals, which together served for 200 patients. In Molde there was also a small hospital, for lepers, so that altogether in the year 1856 there were about 235 lepers in hospital. In 1861 were opened two new asylums, one in Molde, the other in Trondhjem (Drontheim), and as is seen in TABLE IV (p. 145), since that time a large number of lepers have been admitted to these institutions.