Of course, however, there are a considerable number of persons continually returning to England from countries where malarious diseases are common; and these often bear about with them the effects of paludal poisoning which occasionally exhibits itself in the form of neuralgia. Till very lately, however, I had not happened to come across such cases, although at one time and another I have seen and treated a good many persons returned from India and Africa, whence I judge that neuralgia with this special history is less common than many seem to think. In former times, on the contrary, malarioid neuralgias were so common that they forced themselves on the notice of every practitioner. The term "brow-ague," to this day applied by many medical men to every variety of supra-orbital neuralgia, is a relic of the older experience on this point, as is also the very common mistake of expecting all neuralgic affections to present a distinctly rhythmic recurrence of symptoms. In the year 1864 I published the statement[6] that, "in a fair sprinkling" of the cases of neuralgia which present themselves in hospital out-patient rooms, ague-poisoning may be suspected; but I was then speaking rather from hearsay than from my own experience, which, in fact, had yielded no clear cases of this sort of neuralgia, and was till just recently unable to reckon up more than two undoubted and one doubtful case of the affection, in all of which the fifth cranial nerve was unattacked. The periodicity in one of the genuine cases was regular tertian, in the other regular quotidian. A semi-algide condition always ushered in the attacks; but this was gradually exchanged, as the pain continued, for a condition in which the pulse was rapid and locomotive, but compressible, and the strength was further depressed. In both these cases there was unilateral flushing of the face, and congestion of the conjunctiva, to a slight degree, during the attack of pain. The pain became duller and more diffused contemporaneously with the lowering of arterial pressure; and, after the disappearance of active pain, moderate tenderness over a considerable tract round the course of the painful nerves remain for some time. There was no distinct development of painful points in the situations described by Valleix; but it should be remarked that the cases were rapidly cured with quinine, which very probably accounts for this circumstance.