EV. Thanks to your _own_ memory, Ida, for these incidents. That the possession of the faculty of this _impression_ of memory can be demonstrated, we might doubt, were _verbal_ description _only_ employed; but when we see the artist trace the features of a person long lost to us _from memory_, we know that such ideas existed, and were then _re-excited_ in his mind. The power of the intellect in retaining these impressions is wonderful. Cyrus is said to have remembered the names of all his soldiers, and Themistocles those of two thousand Athenians. We have records from Seneca and others, that some will remember, after one perusal or hearing, very long poems; and even have repeated, word for word, the unconnected jumble of a newspaper. Pascal, as we are told by Locke, _never forgot anything_. Almost equally retentive was the memory of my excellent teacher, Sir Astley Cooper, and hence his nearly unexampled accumulation of facts. The memory of Ben Jonson was retentive to perfection, until the fortieth year of his age. In his youth, he could repeat an entire volume after its perusal; nay, even the _whole_ of his own works, or as he quaintly writes, “All that ever I made.” We know that Bloomfield composed his “Farmer’s Boy” in the bustle of a shoe manufactory, and wrote from his memory. ASTR. I have heard that the particles of the body are constantly changing: if so, how can memory _exist_ in the brain? EV. The answer is easy. Because particles of exact similarity are deposited as others are removed. The parts thus regenerated, of whatever _structure_ they may be, still being identical and unchanged in function. If the dream _be_ an inspiration, Astrophel, it is like “a spirit of the past,” and does not “speak like sybils of the future.” But ere I offer some analogies of _waking_ memory, in illustration of the causes of the dream, I must again fatigue you by a glance at the physiology of memory; the origin or mode of impression of a sense, and the mode of recurrence of such impression, _i.e._ the _excitement of the dream_. Aristotle has asserted that senses cannot receive material objects, but only their _species_, or ειδωλον; and Mr. Locke entertained the same idea. For this effect, however, matter must have _touched a sense_, and its impression, as Baron Haller thought, must have been mechanical. For instance, the rays emanating from a body, and impinging on the retina, or an undulation of sound on the labyrinth of the ear, _stamp an image on the brain_, by which, (in accordance with a prior observation on illusion,) some minute change is inevitably effected; some minute _cerebral atoms_ are displaced.