Oyawale, F. A.||Ajetunmobi, A. A.2018-10-112018-10-1120091595-7578Global Journal of Mechanical Engineering 10(1), pp. 57-60ui_art_oyawale_construction_2009http://ir.library.ui.edu.ng/handle/123456789/1963Measuring of temperature in furnaces has been a problem in many research institutes and universities. The objective of this research is to produce a device capable of measuring temperatures in the range of 400 to 1000°C. This research is on the design of a type J or iron-constantan thermocouple. Constantan is an alloy having a composition of 60% copper and 40% nickel. A type J thermocouple was made by twisting iron lead wire and constantan lead wire. A performance evaluation carried out showed that the measurements were reliable at 95% confidence level for temperatures up to 1000°CenSeebeck EflectPeltier EHecZ,Article