New-York tribune., 1879-09-03
MEARAnIC MACuINES.v

Mr.. UPTON. Mr.. Edisons mathematical assistant
road a paper on Tests of Faradic Machines" Fol-
lowing is an abstract:
The title of the paper. "Tcst Of Parade Machines.
arises from the need OF term 10 cover both dynamo
AM, magnetic machines In the naming Of which there
80 much uncertainty at present. This confusion was
rouud troublesome in experimenting where the same
machine could be either q r3aeneto or dynamo. as the
connections happened be made; and II then that
tho maine was proposed by Mr. Edison. II these
machines could be called FaTadic" in honor OF Fara-
day. II would be IN the nature OF o monu-
nent built 10 the memory Of the dscoverer and first
expounder o. principles which they rest AT the
instance O the inventor who had used the discoveries
with 80 Inuon success. This monumen; would be al
enduring one IN the future thousands Of
these machines will be In use for bghtlng purposes aud
for the transm's ssion OF power
Mr. Upton described the methods pursued AZ Mr.. Ed
isons iaboratry by which the value OF The machines
tested He gave an account OF the defects oi exist
ing thermometers some OF when varied from 10 20
por cent IN tbeir readings as tue mechanism IN II
Cptun pointed out the absurdiy or the present IOrs
which either very poor spring balances or scales
N mn rotating bearings, mono beng of nature that
merchant would think OF selling goods wh though Trey
had been used Tor Sc nS energy s,c,.o On r,o
form scale principle Is extremely sinplc that II tie
speed and strain on pei are R'own tns p1wer ny ,a ~
passed under pulley IN inc SAME manner as IN ne
weight on tho platform OF .he scale ana tne ~Ssnt ~
lifted measured So sensitive was tue apparatus tnht
oommutator could be detected when the circult was
open while It's range from Que one-hundredth OF
horse power TO ten horse power.
Mr. Upton gave some tests OF the G-amme machine,
showing that with "A constant hed the eectrOmotiye
force much less the resistance III the circuit
was reduced and pointing cut the relations the
strength OF tue fed and tue currentS oWaDtd as well
as the changes due to variation IN the spoeds.
Tho new machine OF MIR. Edison gives bnck 30 per
cent OF power received IN tho shape OF electricity
The constants tor determining this were the fol-
lowing: The IesistDces were STANDARD box rom Lon
don, tie eIectrouioJve force OF Daniels cell
eu,ned AS one ead eight hundredths volts. and
the foot pounds given on by unit OF cut
rent. one Weber, acting over one ohm was taken
s forty four and threetenths This result ie VeIy
markabio being nearly 10 per cent greater Than from
any other machine In making the measurements MI
nauoimeter made after the drawings Oi Pro-
fessor Ow bridge Of Harvard College was used ami
proved 10 DO AN OF great practical utility
easurng strong Mr. Upton proposed me thod
OF energy in the carbon arc based on toe
principle the distribution ~ work in an electric CIR
cult Is proportional the fan Of teDsion: and he
suggested tho same method Tor studying the
machines. Tine criterion To judge machine
by is the smallest resistance with the greatest
eieotromoiye force, the power consumed IN the
magnets aud the OF nachlue and spark the com
mulator being considered Mr.. Edison had obtained
from IA machine running at 700 revolutions minute,
tension equal l25 cells Of Danrs the arDature hay
ing ONLY sixcnths of Ohm Resistance ana only one
sixth OF a horsepower being CONSUMED IN the magnets