TY - JOUR AU - Parsons, R. A. AU - Schultz, H. B. AU - Lider, L. A. TI - Petroleum coke-based bricks for frost protection JF - California Agriculture JO - Calif Agr Y1 - 1967/01/01 VL - 21 IS - 1 SP - 12 EP - 13 PB - University of California Agriculture and Nature Resources SN - 0008-0845 UR - http://www.ucanr.edu/sites/calagjournal/archive/?article=ca.v021n01p12 AB - Recently a new family of frost protection devices has become available. Heaters are now being made from petroleum wax or coke and molded in various forms, such as candles, bricks or flat trays. Because these devices have a much lower heat output per unit than conventional heaters, and information about their protection ability is limited, preliminary tests were initiated to learn more about this type of heating.