[MILLER & KENRICK] ELECTRICAL MEASURING APPARATUS 101 
TABLE I. 
[1]...0°1...[2]...0°9...[3]..-9...[4].-.90...[5]...900...[6]..-9000...[7] 
[8]..-variable resistance on W...[9] 
MO -101-8. al. -pit...20327.. [121...[0]...1833... M8] 
G...[c]...[14]...1000...[4]...1000...[e]...1000...[15]...[f] 
(A).:.1461-:-10002[07 715. (7) 
fi7]...(110 V.) [20]...Solenoid À  [23]...(+X) [26]...9 fig IX. 
[18]-..(—2 V.) 121]...Inner ring  [24]...(—X) 
[19]...(+2 V.) [22j...Outer ring  [25]...Scraper 
(A) and (k) are binding posts, by means of which [16] and (0 V.) may be connected 
directly. (0 V.) and (110 V.) are binding posts attached to the negativeand positive of 
the 110 volt circuit. (+2 V) and (—2 V) are binding posts communicating with the 
positive and negative terminals of an isolated two volt circuit (storage battery). 
+ X) and (— X) are the terminals of the instrument to which the E. M. F., resist- 
ance, etc., to be measured is attached. ‘‘ Inner ring,” etc., refers to the commu- 
tator, fig. VIII. 
The coils 0.1, 0.9 and 10 ohms are made of heavy wire mounted on wood ; the 
remainder of fine silk-covered ‘“ special resistance wire” wound non-inductively on 
glass tubes, 
The cups [a] to [ f] are situated at one end of the switch board. If [a] be joined 
to [b] by a sign block, the ‘ doubler,” the value of one division on the dial when 
measuring voltage or current is doubled. 
When measuring ohms or mhos, the resistance in series with the galvanometer 
may be lessened by connecting [ f ] to [e], [d] or [e]. 
