Abstract: An apparatus for analyzing and identifying odorant materials includes a plurality of paired thermistors disposed in a tubular chamber. One of each pair of thermistors is coated with one of a number of adsorbing coatings. Each pair of thermistors is electrically connected to form opposite arms of one of a plurality of Wheatstone bridge circuits. A gas sample carrying a vaporized odorant material is drawn by vacuum induction through the tubular chamber. The odorant material is adsorbed to varying degrees by the coated thermistors, depositing latent heat of vaporization on the coated thermistors and increasing the temperatures and resistances thereof. The uncoated thermistor of each pair acts as a stable temperature reference, and the changes in resistance of the coated thermistor disrupts the balance of the bridge circuit.