506 PROCEEDINGS OF SECTION F. 



in charge was one day informed that war signals were being raised 

 by the natives. Ascending an adjacent hill to investigate, two 

 spiral coils of light smoke were observed, the spiral form being 

 given to the smoke by the blacks. Skies held by two natives were 

 kept turning with a circular motion in an inclined plane over the 

 rising smoke, so as to cut the column at each revolution of the 

 skin, and so give a spiral motion and form to the smoke column as 

 it rose, the fire being of dry wood. In the afternoon of the day 

 on which these .•signals were made only three blacks were at the 

 camp, but at daylight next morning between 600 and 700 natives 

 surrounded the camp. These had crossed Port Darwin in their 

 canoes by moonlight dui-ing that night. The warriors were painted 

 and fully armed, thus showing that the previous day's signals were 

 understood and responded to. 



f A large high-towering signal smoke, with an upward whirling 

 motion, and of singular whiteness (raised from spinifex) Avas 

 observed some thirty miles south of east from the Everard Ranges. 

 A native showed afterwards the method of raising the signal. 

 Gathering a pile of very dry spinifex, after firing it, he whirled 

 round the growing flame a heavily ibliaged bough, gradually bring- 

 ing the upward circlings to a point above the pile. Thus a whirl- 

 wind motion was imparted to the air, and so to the uprising heated 

 air and smoke from the burning spinifex. Mr. Charles Winnecke 

 says: — '" I have noticed both the spiral and intermittent forms of 

 smoke, both raised for a special purpose by the selection of. by 

 growth, specially formed bushes, or bunches of grass and spinifex, 

 so turned and twisted by the action of the wind that, by setting 

 fire to them at a carefully and specially selected point, the various 

 degrees and forms of smoke Avill be emitted. The blackfellow's 

 acuteness in instantly observing those traits of nature most service- 

 able to him at the moment enables him readily to select the bush 

 adapted to his purpose. I have seen it too frequently to assume it 

 to be an accidental production."' 



The spiral form of signal seems the one most puzzling to those 

 who find the idea of such a form novel. But if the upward 

 rushing force of the heated air and smoke «ecure a boring whirling- 

 motion of 25ft. to 50ft. let it be supposed that the whirling motion 

 is then lost, the smoke, though now itself inert, being borne aloft 

 would still maintain the spiral form it had first assumed. Con- 

 ceivably a body of smoke (be it of what form it may) borne aioft 

 in an upward current of heated air would maintain that form unless 

 the atmospheric conditions altered so as to play upon its form and 

 change it. The steam from a locomotive in humid conditions of 

 the !iir, especially in still air, maintains the shapes in which it is 

 delivered into the atmosphere for a quite considerable space of 

 time, and for a distance amounting to hundreds of yards from the 

 chimney that emitted it. The simile is apropos only to a limited 



+ Mr. V. H. Edwards, Giles' Exploi-ing E.xpedition, 1882. 



