Wild T4 astronomical theodolite

Wild Heerbrugg T4 for geodetc astronomy and angular measurements in first order networks.

The Wild T4 is world renowned as the ultimate in surveying theodolites, it is one of the largest and most precise micrometer theodolite ever made. Circle readings are read directly to 0.1 arc second horizontally and 0.2 arc second vertically, these circle reading can be estimated to 1/2 that interval.

Betwwen 1941 and 1981 Wild produced a total of only 439 instruments, many them are now on display in surveying instruments museum all over the world 

The Wild T4 Universal Instrument is the largest of the Wild range of theodolites and is used for geodetic triangulation, astronomical observations and-geographical position determinations. Its broken telescope (with 65x magnification) allows comfortable sighting to the zenith. Circle readings are made with an optical micrometer and by coincidence setting of diametrically opposite graduations. The horizontal circle is read directly to 0.1” and the vertical circle is .0.2”. Accessories of equally high precision are also available for use with the T4, such as a chronograph, a chronometer and a time signal receiver.