Telegraph 

 Temperature 



SCIENTIFIC SIDE-LIGHTS 



680 



ments of the senses to the brain, 'or return 

 from the brain to the members out in the 

 world. And just as the brain cannot dis- 

 tinguish from which point in any thread 

 of perception the news of pain has ar- 

 rived, since a knock on the elbow may be 

 felt in the hand, so the telegraph operator 

 cannot know from what station a despatch 

 is being sent until the name of that station 

 is announced. And if at any point the 

 wire is destroyed, tho a mob may riot or a 

 run of ice threaten to destroy, no officials 

 will receive warning. And just so, if the 

 nerves of sensation in a man's leg were 

 paralyzed, the burning of his foot to ashes 

 would not disturb his sleep any more than 

 if that leg were of wood. 



We see, then, that the miracle of our 

 age, the electric telegraph, was prefigured 

 long ago in the animal machine. But the 

 similarity between the two kinds of appa- 

 ratus, the nervous system and the electric 

 telegraph, is still more profound. It is more 

 than similarity; it is relationship, corre- 

 sponding not merely in their effects, but also 

 in their causes. Du BOIS-REYMOND Tie- 

 rische Bewegung (a Lecture), in Virchow 

 und Holtzendorff's Sammlung wissenschaft- 

 licher Vortrdge. (Translated for Scientific 

 Side-Lights.) 



3365. 



Long Preparation 



for Unity of the Host of Discoverers. The 

 ancients discovered the electricity of amber; 

 and Gilbert, in the year 1600, extended the 

 discovery to other bodies. Then followed 

 Boyle, Von Guericke, Gray, Canton, Du Fay, 

 Kleist, Cuna<us, and your own Franklin. 

 But their form of electricity, tho tried, did 

 not come into use for telegraphic purposes. 

 Then appeared the great Italian Volta, who 

 discovered the source of electricity which 

 bears his name, and applied the most pro- 

 found insight and the most delicate experi- 

 mental skill to its development. Then arose 

 the man who added to the powers of his in- 

 tellect all the graces of the human heart, 

 Michael Faraday, the discoverer of the great 

 domain of magneto-electricity. Oersted dis- 

 covered the deflection of the magnetic needle, 

 and Arago and Sturgeon the magnetization 

 of iron by the electric current. The voltaic 

 circuit finally found its theoretic Newton 

 in Ohm; while Henry, of Princeton, who had 

 the sagacity to recognize the merits of Ohm 

 while they were still decried in his own 

 country, was at this time in the van of ex- 

 perimental inquiry. 



In the works of these men you have all 

 the materials employed at this hour, in all 

 the forms of the electric telegraph. Nay, 

 more; Gauss, the celebrated astronomer, and 

 Weber, the celebrated natural philosopher, 

 both professors in the University of Gottin- 

 gen, wishing to establish a rapid mode of 

 communication between the observatory and 

 the physical cabinet of the university, did 

 this by means of an electric telegraph. Thus, 

 before your practical men appeared upon the 



scene, the force had been discovered, its 

 laws investigated and made sure, the most 

 complete mastery of its phenomena had been 

 attained nay, its applicability to telegraph- 

 ic purposes demonstrated by men whose 

 sole reward for their labors was the noble 

 excitement of research, and the joy attend- 

 ant on the discovery of natural truth. 

 TYNDALL Lectures on Light, lect. 6, p. 220. 

 (A., 1893.) 



3366. TELEPATHY Communication 

 without Speech A Possible New Step of 

 Evolution. Is this the end? It is by no 

 means likely. The mind is feeling about al- 

 ready for more perfect forms of human 

 intercourse than telegraphed or telephoned 

 words. As there was a stage in the ascent 

 of man at which the body was laid aside 

 as a finished product, and made to give way 

 to mind, there may be a stage in the evo- 

 lution of mind when its material achieve- 

 ments its body shall be laid aside and 

 give place to a higher form of mind. Tele- 

 pathy has already become a word, not a 

 word for thought-reading or muscle-reading, 

 but a scientific word. It means " the ability 

 of one mind to impress, or to be impressed 

 by another mind, otherwise than through 

 the recognized channels of sense." By men 

 of science, adepts in mental analysis, aware 

 of all sources of error, armed against fraud, 

 this subject is now being made the theme 

 of exhaustive observation. DBUMMOND As- 

 cent of Man, ch. 5, p. 183. (J. P., 1900.) 



3367. TELEPHONE ANTICIPATES 

 THE EYE Passage of Lightning Heard be- 

 fore Flash Is Seen. The sound produced in 

 the telephone by lightning, even when so 

 distant that only the flash can be seen in 

 the horizon, and no thunder can be heard, 

 is very characteristic something like the 

 quenching of a drop of molten metal in 

 water, or the sound of a distant rocket; 

 but the remarkable circumstance for us in 

 this history is that this sound is always 

 heard just before the flash is seen, showing 

 that there is an inductive disturbance of the 

 electricity overhead, due to the distant 

 concentration preceding the disruptive dis- 

 charge. Thus, on November 18, 1877, these 

 peculiar sounds were heard in Providence, 

 and the papers next morning explained them 

 by reporting thunder-storms in Massachu- 

 setts. Sounds like those produced by light- 

 ning, but fainter, are almost always heard 

 many hours before a thunder-storm actually 

 breaks. FAHIE Wireless Telegraphy, p. 80. 

 (D. M. & Co., 1900.) 



3368. TELESCOPE EXTENDS DO- 

 MAIN OF HUMAN MIND Gives Mathe- 

 matics Nobler Problems Perception Reacts 

 upon Thought. The transition from natural 

 to telescopic vision which characterizes the 

 first ten years of the seventeenth century 

 was more important to astronomy (the 

 knowledge of the regions of space) than the 

 year 1492 /that of the discoveries of Co- 



