Eötvös torsion balance model E-54

The automatically rotating and photographically recording Eotvos torsion balance, model E-54, is supplied with excellent torsion wires, built into a balance housing of quadruple wall with layers of air and carefully adjusted so that exterior temperature fluctuations do not influence the positions of equilibrium of the balances. The instrument is photographing upon the plate the scale and the reticle so that the positions of equilibrium of the balances may be read simply by means of a magnifying glass, without any measuring. The instrument is simultaneously photographing the numbers of the instrument and station upon the plate, thus the troubles caused by mistakes or faulty notes are eliminated. — A mechanical device accomplishes the exposure and sets aftewards the instrument in rotation. Actual sensitivity of the balances as to the gradient is 0.255×10−9 CGS=0.255 Eotvos-unit, as to the curvature=0.724 Eotvos-unit referred to one tenth of the scale division, Relaxation time of the balance is 40 minutes. This study proving with original photographs and the interpretation of the same the sensitivity and high reliability of the instrument.