280 REVIEWS. [September, 



of the maximum range occurring on one day as upwards of 100°. 

 He states that the extreme points in one month (June) have been 

 recorded 143° maximum^ 29^° minimum^ and says it is quite pos- 

 sible for these two extremes to happen in the space of twenty- 

 four hours, or rather, in the space of twelve hours, for the maxi- 

 mum is usually about two or 5 p.m., and the minimum about an 

 hour before sun-rising. Have these extremes ever been observed 

 in one day ? Is there any record of such observation ? If there 

 be not, though it may be admitted that it is possible, is it pro- 

 bable? 



Mr. Jenyns states that the mean annual temperature of Swajff- 

 ham Bulbeck is 49°, and that it is only half a degree lower than 

 the mean temperature of London, which in Daniel's tables is 

 entered at 49° 5'''. 



" In the last chapter of his work the reverend author sums up the result 

 of all his observations on the climate of Cambridgeshire, concluding with a 

 calendar of periodic phenomena in the Vegetable Kingdom, extracted from 

 a larger work on the subject, viz. ' Obsei'vations in Natural History,' etc. 

 For this calendar, the reader is referred to the work itself." 



The following account of the malaria prevalent in summer in 

 the fens is interesting both in a botanical and sanatorial view. 

 These fens are unenclosed and undrained, to promote the accu- 

 mulation of peat, which is used as fuel in these parts ; and some 

 part of it was, not many years ago, brought to London for sale. 

 Mr. Jenyns writes — 



" Among the vegetation with which the peat holes or pits are gi-adually 

 filled up are certain species of Chara and Potamogeton, which abound more 

 than any others, and the first of these especially is well adapted for causing 

 a rapid accumulation of vegetable remains at the bottom of the pits by 

 the constant decay of the lower part of its stem, while its upper extremity 

 continues to make fresh shoots. From this cii-cumstance there is soon 

 formed a decomposing mass, which, as the heat of summer partially dries 

 up the water, is exposed to the atmosphere, emitting the most offensive 

 eflluvium. I believe these to be the plants which, dm-ing the putrefactive 

 process, mainly contribute to the miasma that arises from the Cambridge- 

 shire fens." 



In process of time these give places to Hushes, Sedges, Grasses, 

 and other aquatic plants, which rapidly fill up the pits. 



In hot weather the winds that blow over these bogs, more or 



