3 healthy mature rabbits, vary T NMT 1C Received 10mL/kg in ear vein, completing injection within 10 mins after start of administration Rectal temp recorded at 1,2,3 hours injection of 30 mins interval 1 hour after injection Apparatus are depyrogenated at 250C, warm sol. to 37C +/- 0.2C Results: No rabbits showed an ind. - rise of 70.5C otherwise: +5 rabbits