A very infectious disease was at one time common in the poorer parts of Scotland, and known under the name of sibbens, or sivvens, chiefly occurring amongst the poor, ill-fed, badly-clothed, and worse-housed people in the Highlands. It was communicable by very slight contact by kissing the lips of an infected person, smoking the same pipe, drinking out of the same cup, or using the same spoon. Cases of it are still occasionally seen. There are ulcers of the lips, mouth, throat, and nose; ulcerated patches and warty excrescences in the cleft of the thighs, in the axilla, and round the anus and pudenda. A pustular eruption appears, and terminates in hardened crusts. The same disease is known in Ireland, under the name of button-scurvy; and a similar one, called raddesyge, has been described as occurring on the sea-coasts of Norway and Sweden. In Canada, also, something of a like nature was at one time prevalent. The yaws, at one time common and destructive in the West India Islands, appear to be much of the same nature. Some of these diseases, more particularly sivvens, are very common amongst children. Even in these days children are not unfrequently born with copper-coloured blotches of the skin and desquamation of the cuticle; or they may come into the world with these appearances, along with affections of the mucous membrane, hoarse voice, redness round the anus, &c. These are forthwith attributed to a syphilitic taint existing in either of the parents; and one or both are put under mercury; but child after child comes into the world in the same plight. Again, the disease is communicated by children to the nurses, and _vice versâ_. All these affections are rendered much more obstinate by full courses of mercury: the bones and ligaments become affected in consequence; but small doses of that medicine may prove useful towards the decline of the disease. Some have believed mercury a certain test of syphilis; maintaining that the disease, still checked by the specific, is never overcome by the constitution; that it is unchangeable, and regularly and progressively grows worse, where no mercury is employed; that, opposed by that medicine, it is stationary, and is permanently cured by adequate mercurial influence on the constitution. Whatever were the appearances, if they went off under mercury, the advocates for this practice set them down as those of syphilis, lues, or pox. If they did not yield to that mineral, they were termed syphiloid, pseudo-syphilitic, or mercurial; for they did admit, now and then, that their favourite remedy produced unpleasant effects. Such theory and practice are now very happily exploded.