helio-, from Ancient Greek Ἥλιος (Hēlios), from ἥλιος (hēlios, “sun”) + meter, from Frenchmètre, from Ancient Greek μέτρον (metron, “measure”).
Heliometer Sentence Examples
One was to use a heliometer to measure the distance between the limbs of Venus and the sun during the whole time that the planet was seen projected on the solar disk, and the other was to take photographs of the sun during the period of the transit and subsequently measure the negatives.
The present writer has successfully used a similar plan in measuring position angles of a Centauri with the heliometer, viz.
Again, in an ocular heliometer by Steinheil double image is similarly produced by a divided prism of total reflection placed in parallel rays.
Better determinations of the actual value came from the heliometer, and gave an angular diameter of 31' 59.26" =0.10", and the value of the polar diameter exceeded the equatorial by 0.038" =0.023".
To remedy drawback (2) Repsolds provided for the Yale heliometer an additional handle for motion in position angle, intermediate in velocity between the original quick and slow motions.