Experiments show that, of the to
bacco below that still unburnt, about 25 per cent
reached a temperature exceeding 300°C. during
the suction, and at least 60 per cent a temperature
exceeding 100°C. The corresponding fractions of
the substances in the tobacco leaf were thus dis
tilled into the smoke without being burned and
without attaining the higher temperatures at all.

With cigarettes the situation was quite dif
ferent. No essential differences could be noted
among the various brands of cigarette studied
(Groups a-/). The highest temperature recorded,
812°C., was in a Turkish cigarette. The maximal
temperature at the tip was always somewhat low
er. In a thin cigarette with a paper mouthpiece,
the highest temperature, 786°C., was recorded at
the base. Temperature in the combustion zone
was, on the average, 650°C. (variability, 470°-
812°C.). Combustion and distillation zones were
very small : with the glow at the tip, less than 15
per cent of the total quantity of tobacco attained
a temperature of more than 300°C. and less than
25 per cent a temperature above 100° C., while
the condensation zone (below 100°C.) comprised
more than 75 per cent of the tobacco.