Mason's Hygrometer with Wet and Dry Bulb, Wall-Mounted Material_Muslin accepting rods up to three-quarters

accepting rods up to three-quarters of an inch for positioning apparatus at any angle

this two-gap Wheatstone bridge is the standard student apparatus for resistance comparison and verification

the half-size circulatory model traces arterial and venous pathways from heart to peripheral capillaries

Used to supply rechargeable DC power for circuit experiments

this 22 SWG bare copper wire on a 250g reel runs about 225 feet — the workhorse fine gauge of the line

Mason's Hygrometer with Wet and Dry Bulb, Wall-Mounted Material_Muslin accepting rods up to three-quartersWall mounted Mason's hygrometer with two identical dual scale thermometers one dry and one kept wet via a water reservoir calculating relative humidity from their paired reading difference.