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CONTENTS 



Preface 



List of Figures in Text 



List of Plates 



List of Tables 



CHAPTER 



I Historical Introduction .... 

 Speculations on the origin of disease . 

 Early microscopists and the discovery of spores 

 Controversy on spontaneous generation 

 The germ theory of disease 

 The hygienists and their investigation of the air 

 The allergists ...... 



II Sedimentation in Still Air 



Factors determining velocit}' of fall 



Effects of sedimentation .... 



III The Atmosphere as an Environment . 



The atmosphere and its layers 



The troposphere ..... 



Laminar boundary layer 



Local eddy layer ..... 



Turbulent boundary layer 



Transitional or outer frictional turbulence layer 



Convective layer ..... 



Night radiation and temperature inversion 



Role of convection .... 



The stratosphere ..... 

 Circulation of the atmosphere 



Air masses ...... 



IV Spore Liberation 



Problems of 'take-off' .... 



Take-off mechanisms in cryptogams etc. 

 Viruses ...... 



Bacteria ...... 



Actinomycetes ..... 



Myxomycetes ..... 



Fungi ....... 



Lichens ...... 



Algae ....... 



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