es 
THE 
AMERICAN 
JOURNAL OF SCIENCE AND ARS. 
[SECOND SERIES.] 
Arr. XXIX.—On a hid of spoiling , by the Electric spark, 
spark, 
Jigures similar to disse of Licubnbers. by Ext W. Buaxg, Jr. 
LicHTENBERG’s figures, discovered in 1777, are a result of 
the attraction of an electrified surface for light ‘particles of elec- 
film 
eee plate, and the latent image is Gralipe e gore 
€ method I have to describe consists in dasene the dis- 
the ¢ ee the re of a fusible non-conducting ig 5 
€ near its fusing point the figure appears at 
if Ogg a latent AR exists which may be “ aevelaped m by 
“The non-conducting surface is prepared by coating a plate of 
Metal with an even film of tak Pieces of sheet-tin, 3 inches 
“quare, coated with films of pitch of a thickness varying 
tween 0-01 and 0-02 in., were used in most of my experiments. 
the pitch was the ordin commercial article, freed from sand, 
Aus Shellac, rosin, Burgundy-pitch, bees-wax and 
vit balsam we - subst but 
With tory res 
¢ 
. n L pright B ae the 
ug ahey pumaee ae ge: eer be turned in its 
ut is aria ga So from mo longitudinally. The 
am C holds the wire wire slides up Sas down with 
Serena Sey ee ee ae 
