Aerobiology on Commercial Air Routes

Abstract

WHILE I was a passenger from New Zealand to the United Kingdom in September 1947, I was able to expose microscope slides on a stick held out from commercial flying boats, and I trapped as many as 143 pollen grains and 273 fungal spores on 7·5 sq. cm. of adhesive surface exposed for five minutes at 140 knots (about 160 m.p.h.). Proctor¹ outlines a number of complicated constructions for exposure of slides from aeroplanes; but the simple method I have used makes it possible for biologists travelling as ordinary passengers on commercial aircraft to contribute to our knowledge of aerobiology. The method is due to a suggestion by Mr. E. A. Madden of the Department of Scientific and Industrial Research, New Zealand, to run a leading wire before the slides to break up the pressure cone, and to streamline the stick behind in order to prevent turbulence from increasing its apparent width. At the lower speed of their aircraft, this may not have been necessary for the single slides of Polunin et al.²; and of Stakman et al.³; but the larger surface of Stakman‘s multi-slide trap may have required some such provision, and hence its poorer performance. My exposures were made through the astro-hatch of the Empire-class flying boat Aotearoa, over the Tasman Sea, and through the window of the steward‘s pantry on the Hythe flying boat, Hobart, thereafter.