Ce 
157 
On a System of Notation ee to eipiaining to 
Students certain Electrical Operations. 
By the Hon. Proressor Smiru, M.D., M.L.C., C.M.G., &c., 
University of Sydney. 
[Read before the Royal Society of N.S.W., 3 October, 1877.] 
For a number of years I have been in the habit of using in my 
lectures on electricity a simple kind of notation in applyin g the 
double-fluid hypothesis to the ena of Volta’s clectro- 
t the same objection may urged, wit. 
tea or avis force, to any other hypothesis ; Ree if in : teaching 
) make use of any hypothesis pant it has been 
stratio of the bar. 6 thet which would I think be dull work 
for both teacher ais taught: Provisionally then we use the 
fluid hypothesis because it ‘adapts itself readily to all the ordinary 
phenomena, and affords a simple means classifying or con- 
necting them together. De la Rive says of it:—* Although 
subject to strong objections, it is, in ae. resent state of the 
age that implies uli existence of electric fluids. It appears 
thi 
to prove, that when electrical phenomena, as those of induction, 
conduction, insulation and discha sit oceur, 7, depend on ag" 
us particle tter, 
