In this paper the relations between the relative humidity and the elongation of the incense stick, and the effect of weather factors (i.e. relative humidity, temperature and wind velocity) and the inclination of the incense stick on its combustibility were studied. The main results are as follows:1. The dried incense stick, as figures 1 and 2 show, accommodates its length and weight to the state of the surrounding air within about 40 minutes, taking water vapour from it, and remains the same as long as the humidity of the air does not change. On the other hand, after the incense stick has been kept for a few days in a vessel above the water contained in it to saturate it with vapour, it takes about 150 minutes to become the same as the surrounding air condition (figures 3 and 4). This phenomenon is clearly due to histeresis.2. The variation of the velocity of burning when the incense sticks are inclined from the vertical is shown in figure 9. The variation is, most probably, owing to the unequal amount of oxygen supplied to them and the different degrees of heat-conductivity.3. Humidity exercises greater influence than temperature upon the combustibility of the materials, the ratio being 76% against 24% (figure 13).4. The air current has evidently great influence upon the bruning. As figure 14 shows, the velocity of burning, which is 4.17mm/sec. at dead calm, gradually, though slightly, increases with the wind velocity, and when the latter rises to about 1.5m/sec. some of the incense sticks begin to go out and at 3m/sec. all of them completely die out. The interesting fact observed in the figure is that a clearly divergent curve is formed, and we think that it is is due to the smallness of the wind channel we used, the diameter of which is about 35cm.