_Fourth._ She controlled its action so as to give her brother (the professor) a "smart shock when he was several rooms off." (The account states, that when the professor received the shock, "he started up and rushed into her chamber, where she was in bed; and as soon as she saw him, she said, laughing, 'Ah, you felt it, did you?'") _Fifth._ She was subject, also, to spasms and paroxysms of rigor and trembling. Some of the phenomena, in this case, resemble those we see exhibited by the electric fish. The case is an important one in considering the command which the nerve centres possess over the general agents associated with them." We shall now present another singular case, which occurred in this country, in the month of January, 1839, an account of which was given in Silliman's Journal, by a correspondent:-- _First._ That "on the evening of January 28, 1839, during a somewhat extraordinary display of the northern lights, a respectable lady became so highly charged with electricity, as to give out vivid electrical sparks from the end of each finger, to the face of each of the company present." _Second._ That this did not cease with the heavenly phenomena, but continued several months, during which time she was constantly charged and giving off electrical sparks to every conductor she approached. This was extremely vexatious, as she could not touch the stove, or any metallic utensil, without giving off an electrical spark, with the consequent twinge. _Third._ That "the state most favorable to _this phenomena_ was an atmosphere of about eighty degrees Fahrenheit, moderate exercise, and social enjoyment. It disappeared in an atmosphere approaching zero, and under the debilitating effects of fear." _Fourth._ That, "when seated by the stove, reading, with her feet upon the fender, she gave sparks at the rate of three or four a minute; and under the most favorable circumstances, a spark that could be seen, heard, or felt, passed every moment." _Fifth._ That "she could charge others in the same way, when insulated, who could then give sparks to others." _Sixth._ "To make it satisfactory that her dress did not produce it, it was changed to cotton, and woollen, without altering the phenomenon. The lady is about thirty, of sedentary pursuits, and delicate state of health, having, for two years previously, suffered from acute rheumatism and neuralgic affections." For further investigation into the cause of singular phenomena evolved from secret agents, and the true philosophy of biology, magnetism, trance, &c., we would again refer to the numbers of a work by Mr. Rogers, now in process of publication. His principles and deductions challenge successful contradiction. EXPERIMENTS IN BIOLOGY.