Prolonged spastic contraction of voluntary muscles, going on, sometimes for weeks, and even months, is a phenomenon that has often been observed; it may attack the arm only, or may affect all the limbs, and the muscles of the trunk and of the neck: it is for the most part symmetrical, but is occasionally unilateral. It begins in the extremities, and is very commonly limited to them; it is much more gentle than tetanic spasm, and is also painless, or nearly so; but the contraction is often strong enough to resist very vigorous efforts at artificial extension. Paralyses, both of bowel and bladder, have been recorded among the occasional phenomena of spinal irritation with fixed tender points; but I cannot say that I have ever seen such an occurrence. On the whole, I must say that by far the most frequent phenomena of spinal irritation that I have seen have been somewhat diffuse cutaneous or mucous tenderness and irritability (without acute pain) and the presence of tormenting arterial throbbings; also a marked tendency to aggravation of some symptoms, especially the gastric, when firm pressure is made upon the tender spinal points. For a further and fuller account of the phenomena of spinal irritation I may refer the reader to the able article of Dr. Radcliffe,[48] and the work of the brothers Griffin, already quoted; adding the suggestion, however, that both these authorities, and especially the Griffins, appear to me not to draw a sufficiently clear distinction between the class of cases that I have been attempting to describe and the true neuralgias. After what has been said, there is no need to draw out a formal list of the points of diagnosis between spinal irritation and neuralgia. It must be admitted, moreover, that the two forms of diseases have a strong connection in the fact that they are each of them most frequently developed in the descendants of neurotic families. It is by the more generalized character of the symptoms, and the absence of the tendency to perpetual recurrence of paroxysmal pain in one definite nerve, that spinal irritation is mainly distinguishable from true neuralgia. I may add that there is a marked distinction, also, in the results of treatment.