This account is very unworthy a physician, and is a strong evidence that he never felt the heavy effects of this Disorder; otherwise he would have allow’d it to be a real Disease of the Body.
A metaphysician has laid great stress on this Disease, as an argument in defence of some of his wild opinions. He asserts, That it is owing to the operation of certains demons, which impose on, and torment, the mind in sleep[4].
This ingenious hint he took from Bellini, who probably stole it from Paracelsus’s doctrine of Archeus faber[5].
The ingenious Doctor Lower is the first author I met with, who observ’d the horizontal position of the Body, and assign’d it as a remote cause of this Disorder, but seems to attribute it immediately to a collection of Lymph in the fourth Ventricle of the Brain.
He says, “Si supine dormiant, Ventriculus ille quartus, Lympha nimium distensus, Medullam Oblongatam sua gravitate premit, ideoque fluxum liquidi Nervosi in Nervis cordi & respirationi inservientibus impedit[6].”
Perhaps he did not apply his first observation so well as might be expected from one of his abilities; for it seems needless to wait for a slow secretion of Lymph to produce this Disease, since, according to his own account, the return of the Blood from the Head, by the Jugular Veins, is in some measure prevented, and by that means a greater quantity of Blood than usual will be collected in all the vessels of the Brain; which might better answer his purpose, and more effectually obstruct the nervous influence. But before either of these causes could be removed by common methods, life would be at an end, and every fit of the Night-mare would be mortal; but that it often happens otherwise, many can testify. Doctor Lower seems to have founded this theory on the dissection of a Man who died of a Hydrocephalus, and not immediately of the Night-mare: hence that case is ill applied by Bonetus[7].