Encyclopaedia Britannica > Volume 8, DIA-England

•570 ELECTRICITY.
Ilistory. silently; and if the cloud was highly charged, the elec- Immediately after the accident the house was filled with ti
-v trie fire would strike in preference the elevated conduc- a sulphureous vapour. A clock which stood in the corner W
p- ,i P t0r^'i T pfthe adjoining room was stopped; the ashes from the
eath ot I he attention of Luropean philosophers was now di- hearth were scattered about the room ; the door-case of
I ti durian" i° t^e 8reat discovery of Franklin, and various in- the room was rent asunder, and a piece of the door itself
a d. 1753. (!lvldua s fearless1^ S0US,U. t0 repeat his experiments, actually torn off. The Leyden jar was also broken, and
Among these Professor Richman of St Petersburg was the metallic filings which it contained thrown about the
one of the most enterprising. He had undertaken a se- room.
ries of experiments on the electricity of the atmosphere, One of the most active and ingenious labourers in theiv,
and for this purpose he had erected an electrical gnomon, field of electrical science was our countryman Mr JohnCantoi
which consisted mainly of a Leyden jar, communicating Canton. Before his time it had been assumed as indisputable A-D-1‘
with an iron rod, which rose four or five feet above the that the same kind of electricity was invariably produced
roof of his house, and an electrometer formed of a linen by the friction of the same electric ; that glass, for exam-
tliread with half a grain of lead, the angular ascent ot pie, yielded always vitreous, and amber always resinous
which on the face of a divided quadrant indicated the electricity. Having roughened a glass tube by grinding
^orce L^e accumulated electricity. On the 9th August its surface with emery and sheet lead, he found that it
1752 Professor Richman obtained from the end of the possessed vitreous or positive electricity when excited
lod electrical flashes which could be heard at several feet with oiled silk, but resinous electricity when excited with
ot distance ; and if any person touched the apparatus, new flannel. He found, in short, that vitreous or resi-
a sharp stroke was felt in the hand and arm. On the nous electricity may be developed at wdll in the same tube,
31st May 1753 the electric fire exploded from the appa- by altering the surfaces of the tube and the exciting rub-
ratus with such a force that it was heard at the distance ber, and according as the one or the other is most affect-
of three rooms from the apparatus. On the 6th August ed by their mutual friction. This he illustrated by the
1153 the professor had prepared and adjusted his appa- very beautiful experiment of removing the polish from
latus, and having heard the sound of distant thunder, he one half of the tube. In this case the different electrici-
left a meeting of the Academy of Sciences, and took with ties were excited with the same rubber at a single stroke,
him his engineer, Mr Sokolowr, to draw any interesting and, what is very curious, the rubber was found to move
phenomena that might occur. On their arrival at the much easier over the rough than over the polished half.
professors house, the plummet of the electrometer was Mr Canton likewise discovered that glass, amber, seal-
elevated four degrees from the perpendicular; and while ing-wax, and calcareous spar, were all electrified posi-
the philosopher was describing to his friend the dangerous tively when taken out of mercury; and hence he was led
consequences that might take place if the thread should to the important practical discovery, that an amalgam of
rise to 45 , a tremendous burst of thunder terrified the mercury and tin was most efficacious in exciting glass when
imperial city. Richman leant his head over the gno- applied to the surface of the rubber. Mr Canton found also
mon to observe the indications of the electrometer, and that any body placed within the electric atmosphere of
m tins stooping position, with his head a foot from the another body acquired the electricity opposite to that of
iron rod, a huge globe of bluish-white fire, about the size of the body in whose atmosphere it was placed; and that
Mi Sokolow s fist, shot from the iron rod to the professor’s the whole air of a room could be electrified either po-
head, with a report like that of a pistol. I he blow was sitively or negatively, and made to retain it for a consider-
fatal; he fell back upon a chest and instantly expired, able time.
Sokolow was stupified and benumbed by a sort of steam or Signor Beccaria, a celebrated Italian, kept up the spi-Beccar
vapour, and the red hot fragments of a metallic wire struck rit of electrical discovery in Italy; and in his work on na-Ai11' f
11s clothes and covered them with burnt marks. As tural and artificial electricity, he has given us the results
soon as he lecovered fiom his surprise, Sokolow ran out of many important original investigations. He showed
of the house, acquainting every person with the accident that water is a very imperfect conductor of electricity,
which had taken place. In the mean time Madam Rich- that its conducting power is proportional to its quantity,
man, alarmed by the thunder-stroke, hastened to the and that a small quantity of water opposes a powerful re-
c lumber, and found her husband apparently lifeless, in sistance to the electric fluid. He succeeded in making
t ie attitude of sitting upon the chest, and leaning against the electric spark visible in water, by discharging shocks
tie wa . Medical aid was instantly obtained, but though through wires that nearly met in tubes filled with water,
a vein was opened, from which no blood would flow', and In this experiment the tubes, though sometimes eight or
though every attempt was made to restore life by violent ten lines thick, were burst in pieces. Beccaria likewise
friction and other means, they were all fruitless. A small demonstrated that air adjacent to an electrified body
quantity of blood dropped from the mouth when the body gradually acquired the same electricity; that the electri-
was turned, and on the forehead there was a red spot, city of the body is diminished by that of the air; and that
10m the pores of which a few drops of blood oozed out. the air parts with its electricity very slowly. He con-
oeveral red and blue spots, like leather shrunk by burning, sidered that there was a mutual repulsion between the
w ere found on the left side, the back, and other parts of the particles of the electric fluid and those of air, and that in
ory. I he shoe upon the Professors left foot was burst the passage of the former through the latter a temporary
open, and a blue maik appeared on the foot beneath the vacuum was formed.
a-peiture. Ihere was no corresponding hole in the stock- The science of electricity owes several practical as well Symme
ing, and the coat was uninjured. When the body w'as as theoretical observations to our countryman Mr Robertexpen-
opened, twenty-four hours after death,there was no appear- Symmer. In pulling off his stockings in the evening, Mrnienb’
ance of injury either in the brain or the cranium: a little Symmer had often remarked that they not only gave aA'D' '
extiavasated blood appeared in the cavities below the crackling noise, but even emitted sparks in the dark. The
lungs, mid in the lungs towards the back, which were of electricity was most powerful when a silk and a worsted
a dark brown colour. I he heart, glands, and smaller in- stocking had been worn on the same leg, and it was best
testines, were all inflamed; but the entrails were unin- exhibited by putting the hand between the leg and the
jured. About seventy rubles of silver which were in the stockings, and pulling them off together. The one stock-
jeft coat pocket were not altered by the electric fluid, ing being then drawn out of the other, they appeared more