156 



Prof. B. Stewart on the Variations [June 15, 



living matter may and does originate independently during the progress 

 of fermentation in previously germless fluids. 



As a result of the fermentative changes taking place in boiled urine 

 or other complex organic solutions, many new chemical compounds are 

 produced : gases are given off, or these with other soluble products mix 

 imperceptibly with the changing and quickening mother -liquid, in all 

 parts of which certain insoluble products also make their appearance. 

 Such insoluble products reveal themselves to us as specks of proto- 

 plasm, that is of ' living' matter; they gradually emerge into the region 

 of the visible, and speedily assume the well-known forms of one or other 

 variety of Bacteria. 



These insoluble particles would thus in their own persons serve to 

 bridge the narrow gulf between certain kinds of ' living ' and of ' dead ' 

 matter, and thereby afford a long-sought for illustration of th e transition 

 from chemical to so-called ' vital ' combinations. 



XV. On the Variations of the Daily Range of Atmospheric Tem- 

 perature as recorded at the Kew Observatory.^' By Balfour 

 Stewart^ LL.D.. E.R.S., Professor of Natural Philosophy at 

 Owens College^ Manchester. Received May 25, 1876. 



(Abstract.) 



The daily temperature-range was selected as an element which affords 

 a good indication of the varpng meteorological activity of the place, and 

 the observations of which can be easily made and reduced. 



The records of the Kew Observatory were chosen because there the at- 

 mospheric temperature has been very carefully observed during a long 

 series of years. The writer desires to thank the Kew Committee for 

 giving him access to the records of the maximum and minimum tempera- 

 tures taken at the Kew Observatory. 



Twenty-one years of these records have been reduced, beginning with 

 the year 1855 and ending with 1875. Two complete sun-spot periods 

 are embraced in these observations. 



The first Table exhibits (a point abeady well known) the annual variation 

 of the temperature-range, which is greatest in summer and least in winter. 



The same Table shows that the yearly means of this element exhibit con- 

 siderable fl.uctuations amongst themselves. Thus we have corresponding 

 to the years 1856, 1866, and 1875 the values 12°-69, 13°-61, and 13°-25 

 respectively, while corresponding to the years 1859 and 1870 we have the 

 values 14'^-52 and 15°-63. 



Inasmuch as the three former are years of minimum, and the two latter 

 years of maximum sun-spots, this would seem to show that the daily tem- 

 perature-range is least for minimum and greatest for maximum sun-spot 

 years. 



