After describing the experience that was the cause of so much misery he continues: "

I trembling waked, and for a season after

Could not believe but that I was in hell,

Such terrible impression made my dream.

Bond" is equally emphatic: "I have often been so much oppressed by this enemy of rest, that I would have given ten thousand worlds like this for some Person that would either pinch, shake, or turn me off my Back; and I have been so much afraid of its intolerable insults, that I have slept in a chair all night, rather than give it an opportunity of attacking me in an horizontal position."

Macnish," in the more distended style that is his characteristic, says: "There is something peculiarly horrible and paralyzing in the terror of sleep. It lays the energies of the soul prostrate before it, crushes them to the earth as beneath the weight of an enormous vampyre, and equalizes for a time the courage of the hero and the child. No firmness of mind can at all times withstand the influence of these deadly terrors. The person awakes panicstruck from some hideous vision; and even after reason returns and convinces him of the unreal nature of his apprehensions, the panic for some time continues, his heart throbs violently, he is covered with cold perspiration, and hides his head beneath the bedclothes, afraid to look around him, lest some dreadful object of alarm should start up before his affrighted vision. Courage and philosophy are frequently opposed in vain to these appalling terrors. The latter dreads what he disbelieves; and spectral forms, sepulchral voices, and all the other horrid superstitions of sleep arise to vindicate their power over that mind, which, under the fancied protection of reason and science, conceived itself shielded from all such attacks, but which, in the hour of trial, often sinks beneath their influence as completely as the ignorant and unreflecting hind, who never employed a thought as to the real nature of these fantastic and illusive sources of terror. The alarm of a frightful dream is sometimes so overpowering, that persons under the impression thus generated, of being pursued by some imminent danger, have actually leaped out of the window to the great danger and even loss of their lives."

2 Op. cit., 1. 61.

Bond. Op. cit., p. 71.

Macnish. Op. cit., p. 68.

The second cardinal feature in the attack is the sense of stifling oppression, as of an overpowering weight, on the chest that impedes the respiration often to the extreme limit of endurance. Radestock" regards this inhibition of respiration as the central symptom of the attack: "Steigert sich die Athembeklemmung zur Athemnoth, welche im Wachen als beschwerliches Athemholen empfunden wird, so entsteht das vielgefürchtete Alpdrücken." Erasmus Darwin," on the other hand, maintained that there cannot exist any actual difficulty of breathing, since the mere suspension of volition will not produce any, the respiration going on as well asleep as awake; he, therefore, doubted the observation. Waller" pertinently remarked to this that "any person that has experienced a paroxysm of Night-mare, will be disposed rather to give up Dr. Darwin's hypothesis than to mistrust his own feelings as to the difficulty of breathing, which is by far the most terrific and painful of any of the symptoms. The dread of suffocation, arising from the inability of inflating the lungs, is so great, that the person, who for the first time in his life is attacked by this 'worst phantom of the night,' generally imagines that he has very narrowly escaped death, and that a few seconds more of the complaint would inevitably have proved fatal."

The third typical feature of the malady is the utter powerlessness, amounting to a feeling of complete paralysis, which is the only response of the organism to the agonizing effort that it makes to relieve itself of the choking oppression. Many writers, such as Kelle," Hodgkin," etc., put this in the forefront of the picture, and Macnish" rightly considers it a diagnostic feature in distinguishing Nightmare from other forms of unpleasant dreams. He writes: "In incubus, the individual feels as if his powers of volition were totally paralyzed; and as if he were altogether unable to move a limb in his own behalf, or utter a cry expressive of his agony. When these feelings exist, we may consider the case to be one of

"Kelle. Du Sommeil et de ses accidents. Thèse de Paris, 1900, No. 254, p. 23.

"Hodgkin. Brit. Med. Journ., May 16, 1863, p. 501.

nightmare: when they do not, and when, notwithstanding his terror, he seems to himself to possess unrestrained muscular mo tion, to run with ease, breathe freely, and enjoy the full capability of exertion, it must be regarded as a simple dream.” Erasmus Darwin," indeed, held the view that the malady was nothing more than too deep a sleep; " in which situation of things the power of volition, of command over the muscles, of voluntary motion, is too completely suspended; and that the efforts of the patient to recover this power constitute the disease we call Night-mare.”

The relation to one another of the members of this triad of symptoms is admirably portrayed by Cubasch" "zu einer belieb igen Stunde der Nacht fühlt der Träumende plötzlich, oder nach und nach, dass die Respiration behindert ist; irgend ein Wesen, meistens ein zottiges Thier, oder eine hässliche menschliche Gestalt stemmt sich dem Schläfer auf die Brust, oder schnürt ihm die Kehle zu, und sucht ihn zu erwürgen; die Angst wird mit der Athemnoth immer grösser, jede Gegenwehr ist unmöglich, denn wie durch Zauberkraft sind alle Glieder gelähmt; der Unglückliche sucht zu fliehen-umsonst, er ist wie angewurzelt an die Stelle; die Gefahr, die Angst wird immer grosser, da endlich überwindet eine letze furchtbare Kraftanstrengung das feindliche Wesen, eine heftige Bewegung erweckt den Träumenden aus seinem Schlafe und-Alles ist vorüber, nur der kalte Schweiss auf dem ganzen Körper, ein laut hörbares Herzklopfen erinnert den Erwachten an den verzweifelten Kampf auf Leben und Tod, an die grässliche Todesangst, die er soeben zu überstehen hatte. Dieses sind in Kürze die Erscheinungen des Alps; nie fehlende Symptome sind die Athemnoth und die mit ihr vergeschwisterte Angst, das Gefühl eines schweren Körpers auf der Brust, das Unvermögen, irgend welche Gegenwehr zu leisten, oder irgend eine Bewegung zu machen."

At the culmination of the attack there are commonly present many accessory evidences of the effort with which the patient, in a mortal panic, has escaped; such are, an outbreak of cold sweat, convulsive palpitation of the heart, singing in the ears, sense of pressure about the forehead, a terror-stricken countenance. Many