SCIENCE, INVENTION, DISCOVERY. 



341 



human skeletons were found in an apparent 

 state of complete petrifaction on the Island of 

 Guadaloupe early in the present century. One 

 of these was placed in the British Museum, 

 and the other in the museum at Paris. But 

 examination showed that in these the bony 

 structure still remained, though it was com- 

 pletely incased in the calcareous deposits. In 

 excavating in the cavern of Mentone, in 

 France, on the coast of the Mediterranean, 

 some fifteen years ago, M. Riviere, a noted 

 French scientist, found a number of human 

 bones and a complete skeleton in a true fossil 

 condition, which were complete evidence of 

 the existence of men upon the earth at a period 

 of very great antiquity. 



Phonograph. The phonograph is a 

 machine for recording and then transmitting 

 sounds, speech, music, etc. It is the invention 

 of Thomas A. Edison, the most noted electri- 

 cian of this age. The phonograph was acci- 

 dentally discovered. Mr. Edison was at work 

 on an apparatus for recording a telegraphic 

 message, by having an armature (with a needle 

 fastened in one end) of the sounder make in- 

 dentations on a piece of tin foil wrapped 

 around a cylinder. The message would thus 

 be punctured or indented on this tin foil, then, 

 by substituting another needle blunt for 

 the sharp one and turning the cylinder, the 

 armature would be vibrated as the needle en- 

 tered into and passed out of the indentations. 

 While experimenting, he turned the cylinder 

 very rapidly, and instead of a succession of 

 " clicks," a musical sound was produced. He 

 seized the idea, and the Edison phonograph is 

 the result. 



The perfected phonograph of to-day consists 

 of a cylinder of wax, or other plastic material, 

 which is revolved either by hand, foot power, 

 or an electric motor. This cylinder, called the 

 phonogram, is used for recording- the sound. 

 This is done by a diaphragm such as is used 

 in a telephone into the center of which is 

 fastened a sharp needle, which rests upon and 

 just touches the phonogram. When the words 

 are spoken the diaphragm vibrates, moving 

 this needle up and down, and a series of in- 

 dentations are made in a spiral line on the 

 phonogram, which is turning around about 

 eighty-five times a minute. To make the 

 phonograph speak, or repeat the words, an- 

 other diaphragm, similar to the first or re- 

 corder, but having a blunt instead of a sharp 

 needle, is placed at the starting point and the 

 phonogram made to revolve ; of course, as the 

 needle passes over the indentations it vibrates 

 the diaphragm and the words are reproduced, 

 as in a telephone. 



The phonograph faithfully reproduces mu- 



sic, whistling, singing, speech, or any sounds, 

 and the phonograms can be packed into a 

 mailing tube and sent all over the world to be 

 used as often as desired. 



Phosphorescence is the property which 

 some bodies possess of being luminous in the 

 dark without the emission of sensible heat. 

 There are five kinds distinguished by physicists, 

 and designated as follows : Spontaneous phos- 

 phorescence ; phosphorescence from the effects 

 of heat ; from mechanical action ; from the 

 action of electricity ; by insoUtion or exposure 

 to the light of the sun. The first is by far 

 the most common and familiar phenomenon, 

 being exhibited by certain living organisms 

 both in the vegetable and animal kingdoms. 

 There are flowers of a bright red or yellow 

 color which have been observed to emit light 

 flashes in the dark, and other plants which 

 give out a faint, continuous light, caused prob- 

 ably by the oxidation of some hydro-carbon 

 which they secrete. The best known exam- 

 ples, however, are those seen in animals, as 

 the glow-worm or firefly, and the myriads of 

 minute animalcula which cause the magnifi- 

 cent displays of phosphorescence that are often 

 seen at sea by night, especially in the tropics, 

 and in temperate zones during the summer. 

 Various causes have been assigned for this ani- 

 mal phosphorescence, and they doubtless vary 

 with different animals. In the glow-worm and 

 firefly it is thought to be produced by an act of 

 the will. M. Jousset discovered the liquid 

 which exudes from the crushed eggs of the 

 glow-worm to be phosphorescent, and to re- 

 main so until dried up. In the marine ani- 

 malcula, it is believed that a subtle luminous 

 matter is thrown off as a secretion supplied by 

 glands having this special function ; and some 

 naturalists assert that it contains epithelial 

 cells in a state of fatty degeneration, the de- 

 composing fat being the cause of the phosphor- 

 escence. That phosphorescence seen in de- 

 caying fish and other animal matter, and in 

 wood (called "fox-fire"), is due to a species 

 of slow combustion by which vibrations are 

 excited capable of emitting luminous rays. The 

 other kinds of phosphorescence are, for the 

 most part, seen only in scientific experiments, 

 except the last, which is now receiving some 

 application in articles of everyday use, as 

 matchboxes, clock-faces, etc. ; they are covered 

 with a preparation possessing this property, 

 and remain luminous, and therefore easily vis- 

 ible in the dark. Certain compounds have 

 been discovered which exhibit the property in 

 a high degree, as Canton's phosphorus, Bo- 

 lognese phosphorus, etc. It is probably due 

 to the absorption of the energy of the vibra- 

 tions falling upon them, which is afterward 



