A TREMENDOUS ARMY OF 
Spencer Microscopes 
Responded at the first call and 
every subsequent call and 
WENT TO WAR 
2 To do 
Uncle Sam’s finest and most exacting work in saving 
the health and lives of oyr noble boys. 
They will soon come back to the universities, col- 
leges and schools with the boys to resume the critical 
duties of peace. 
With greatly enlarged facilities, we hope soon to 
be able to offer better service in supplying all kinds of 
Scientific and Laboratory Instruments than ever be- 
fore. Let us know your needs. 
BUFFALO, N. Y. 
SPENCER LENS COMPANY 
The L. & N.. 
High oe Golyannmetey 
Aninstrument 
of extremely 
high sensitivity, 
ae yet. one with 
“* which it isa 
‘- pleasure to work 
ecausé it is very 
easily set up and 
its working char- 
acteristics are all 
that could be de- 
sired. 
. If you have 
any research 
work involving 
the use of a gal- 
vanometer of high sensitivity this instrument 
can be built to. your order, giving you the 
maximum sensitivity under your working con- 
ditions. 
We solicit correspondence ftom those who are look- 
ing for an out-of-the-ordinary galuanometer 
THE LEEDS & NORTHRUP CO. 
_ 4921 Stenton Avenue 
PHILADELPHIA | 
BUFFALQ 
ee 
Tycos 
Temperature Instruments 
Mercurial, Recording and 
Index Thermometers for 
all industrial and labor- 
atory applications. 
Electric Contact Ther- 
‘mometers. 
Temperature Pressure and 
Time Regulators. 
Mercury Column Vacuum 
Pressure and U Gauges. 
Base Metal,Rare Metal and 
Radiation Pyrometers. 
Fery Radiation Pyrom- - 
eters. _ 
Huerometers 
Hydrometer: 
Mineral Oil Testing Tnstru- 
ments. 
Aneroid Barometers 
Mercurial Barometers 
Recording Barometers 
Pocket Compasses 
Surveying Compasses 
Rain Gauges. 
Anomometers. 
Meters. 
Thermographs. 
Hand Levels. 
Aviation Barometers. 
Inclinometers. 
Sphygmomanometers. 
Fever Thermometers. 
Urinary Glassware. 
Thermometers of all kinds 
for home and General Use. » 
the trade- 
TY COS, ase 
an organization manu- 
facturing indicating,re- 
cording and controlling 
Temperature Instru- 
ments of the beiter type, 
giving utmost satisfac- 
tory service ; an organ- 
ization that serves its 
trade sincerely in all 
dealings. The convinc- 
ing proof of high quality 
of product is its growth. 
Correspondence in- 
vited. We will do our 
best to give you the in- 
formation desired, and 
not subject you to a 
long and mechanical 
series of follow-up let- 
ters. 
Taylor Instrument Co.’s 
ROCHESTER, N. Y. 
There’s a Tycos and Taylor 
Thermometer for everypurpose | 
