]6G REV. M. J. BERKELEY. 



The pains which he has taken to collect all accessible previous 

 information on the subject, and the entire freedom from all 

 prejudice, added to an accurate knowledge of the minuter 

 forms of vegetation and of animal organisms, are amply 

 manifested in the valuable treatise which has lately been 

 received in this country from Calcutta.^ 



The work commences with a review of the literature of 

 Atmospheric Micrography, the necessity for which is thus 

 stated : " Similar observations have been previously recorded 

 by numerous dther authors, and before proceeding to those 

 forming the subject of the present report, it may be well 

 briefly to review the literature relating to them, with a view 

 to ascertain what our knowledge of the question really 

 amounts to. It is the more desirable to do this as no 

 general summary of the kind has, as far as I know, ever been 

 attempted, and the information is scattered through scientific 

 journals and the transactions of learned societies in isolated 

 papers, many of Avhich are, when taken separately, likely to 

 lead to very imperfect conceptions regarding the subject^s a 

 whole. In attempting anything of this kind I am well aware 

 that the result is likely to contain numerous omissions and 

 other imperfections, more especially in a country such as this, 

 where there is great difficulty in obtaining access to the 

 requisite information, but, such as it is, it may yet be of use 

 in rendering the latter part of the report more intelligible 

 than it might otherwise be, and in facilitating an estimate of 

 the value of any conclusions there stated. A chronological 

 order has been as much as possible adhered to, the first obser- 

 vation recorded by any author being taken as a starting point 

 for a sketch of his after work ; and where this is not so, or 

 Avhen due prominence does not seem to have been given to 

 any set of observations, the error is to be entirely ascribed to 

 lack of information, and not to any desire to undervalue or 

 neglect any one's work." 



The observations were made at the two large jails in Cal- 

 cutta, with the view of determining, if possible, whether there 

 were any connection traceable between the prevalence of any 

 special bodies in the atmosphere, and the occurrence of par- 

 ticular forms of disease. They were fifty-nine in number, the 

 date of the first being the 26th of February, and that of the 

 last the 18th of September, 1872. ~ The apparatus was a 



' 'Microscopic Examinations of Air,' by D. Douglas Cunningham, M.B., 

 Surgeon H.M. Indian Medical Service (ou special duty), attached to Sanatory 

 Commissioner with Government of India. Calcutta, Fol. p. 78, tab. xiv, 

 Diag. iv, fig. 10. 



- The climate at Calcutta is very dry from the former date to the begiuu- 



