106 TEACHING SCIENCE IN SECONDARY SCHOOLS


Prism, flint glass, 45 and 90
:Iceland spar, for double refrac-
 tion


*Diffraction grating
'Polariscope, simple
*Spectroscope, direct


Add, as Soon as Practicable
 '"Optical disc and attachments


vision


*Post card projector
*Tourmaline tongs


Magnetism


Dipping needle
Polarity rods

Blue-print paper
Wire, annunciator, or "bell"
 Purchase
 Compasses, small
 Magnets, bar type
*Natural lodestone


 Improvise
 Electromagnets
 Solenoids
securee Locally
 Large knitting needles
 Tacks, nails, etc.
e from Supply House
 Iron filings, or powder
 Magnets, horseshoe type


Condenser plates
Electrophorus
Electric plumes, paper
Induction cylinders
*Leyden jar, large
Pith balls, corn pith

Cloth, woolen, silk
 PG
 Gold leaf


Static Electricity
 Improvise
 *Egg, covered with tin foil
 Electroscopes, gold leaf
 Friction rods, glass, rubber, wax
 Leyden discharger
 Leyden jars, small
 Proof planes
 Secure Locally
 Fur, such as catskin
purchase from Supply House
 Tin foil


 Add, as Soon as Practicable
 Leyden jar, students' removable *Static machine
 type *X-ray tube and fluroscope
*Vacuum and Geissler tubes
 Current Electricity
 Improvise


Cells, simple voltaic
'Electrolysis outfit
*Plating outfit


Contacts and binding posts
Galvanometers, simple
Primary and secondary coils