that antimony, strongly heated with a burning glass, undergoes an increase of weight which can be attributed to nothing else but these particles.

Mayow argued that the same particles are consumed in respiration, because he found that when a small animal and a lighted candle were placed in a closed vessel full of air the candle first went out and soon afterwards the animal died. However, if there was no candle present the animal lived twice as long. He concluded that this constituent of the air is absolutely necessary for life, and supposed