What device measures the temperature inside a kiln?

• A. Kiln
• B. Grog
• C. Pyrometric Cones
• D. Bisqueware

Answer: (C)

Measuring the heat work inside a kiln is done with pyrometric cones. These small ceramic cones bend or slump at specific temperatures for a defined period, so they reflect the actual heat work the ware experiences rather than just the air temperature inside the kiln. When a cone bends to its designated point, it signals that the firing has reached the desired maturity for glaze and clay body, helping prevent underfiring or overfiring since heat transfer can vary with loading and kiln conditions. The other items aren’t measurement tools: a kiln is the furnace, grog is an additive to clay, and bisqueware is pottery that has already been fired once.