File:The journal of mental pathology (1906) (14586232290).jpg

Identifier: journalofmentalp08newy (find matches)
Title: The journal of mental pathology
Year: 1906 (1900s)
Authors:
Subjects: Pathology Mental illness Pathology Mental Disorders
Publisher: New York : State Publishing Company
Contributing Library: Francis A. Countway Library of Medicine
Digitizing Sponsor: Open Knowledge Commons and the National Endowment for the Humanities

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rapidity ofthe makes and breaks depends on the rapidity of the vibrationsof the steel ribbon. Suppose the ribbon vibrates 15,000 timesper minute; the direct current is then interrupted 15,000 timesper minute. The direct current thus interrupted is then led to asecond vibrator, at the second coil, causing say 5,000 interrup-tions per minute; the direct current is now interrupted 20,000times per minute; this interrupted current is now led to a thirdinterrupter, at the third coil, causing, say, 5,000 interruptions perminute; the direct current is now being interrupted 25,000 timesper minute. Each interrupter can be regulated to give more in-terruptions, so that the direct current may be interrupted some40,000 to 50,000 times per minute. A voltmeter in shunt and amilliamperemeter in series measure the current used. Relative physiologic value of direct and interruptedCURRENTS FOR PURPOSES OF RESUSCITATION.—Physiologically thedirect current causes less marked cardiac and respiratory reac-
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u o c U 0061I -ON IIIA ^OA AyOlOHlVd IVXNHJAI dO ^IVN^iaOi aHX PHYSIOLOGIC EFFECTS OF A NEW CURRENT.—Dr. Robinovitch. 197 tions, than does the same current when interrupted; and slow in-terruption causes less marked reactions than does rapid interrup-tion, as is explained below. One of us in the laboratory took into his hands the electrodesin the circuit of a simple direct current. The circuit was sud-denly closed with a switch, the meters registering 20 volts and2.5 milliamperes; the energy of muscular contraction was notedarbitrarily as i. This direct current was now interrupted 15,000times per minute; the circuit was closed as before, and the me-ters showed 20 volts, but only 1.5 milliamperes, and the energyof muscular contraction was 3 times stronger than was that ob-tained with the direct current. Finally, the current was inter-rupted with the second interrupter 20,000 per minute, the circuitclosed as before; meters showed 20 volts, only 0.5 milliamperes,but the energy of muscu

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