Lambrecht Polymeter: A Combination of Hair Hygrometer and Mercury Thermometer. This hygrometer-thermometer instrument combination allows reading of relative and absolute humidity, temperature, dew point temperature, saturation pressure and partial pressure of the water vapor. The measuring element of the hygrometer consist of a group of treated human hairs 20 cm long. The scale is made from anodized aluminum with a silvered background and black inscription. Wilhelm Lambrecht, the founder of the company, started manufacturing meteorological measuring instruments in 1859 in his Gottingen workshop.