Tangent Galvanometer for Magnetic Field Measurement Subcategory_Botany Models or batteries required

or batteries required

Lead-free five-cylinder equal-mass set at 30g each in zinc

the protective coating shielding glassware surfaces from nicks

Four 153 x 76mm plates - each holding 98 iron-rod plotting compasses in a 14 x 7 matrix - assemble flat or as the faces of a cube to display 2D and 3D field-line patterns

and pyloric regions with internal rugae

Tangent Galvanometer for Magnetic Field Measurement Subcategory_Botany Models or batteries requiredTangent galvanometer instrument that derives current absolutely from compass needle deflection against Earth's horizontal field, the basis for classic determinations of the local BH constant.