Analyses of Books. 145 



11. Of these 1564, 1119 were below 13 years of age, and 

 only 66 cases between 41 and 78 years. The English cases 

 are also accounted for on the same principles. Lisfranc 

 gives little credit to the statements of Cheselden, Petrunti, 

 Pajola, &c, for, according to the most recent returns from 

 the Neapolitan hospitals, the loss was 1 in 7. He infers, 

 therefore, that Velpeau has under-rated the success of litho- 

 trity, and over-rated that of lithotomy. He observes, that 

 lithotrity is indicated, 1. Where the calculus is small, and 

 the urinary organs healthy. 2. Calculus a little larger, 

 with a healthy bladder. 3. Two small calculi, healthy 

 bladder. 4. Three small calculi, bladder healthy. 5. Cal- 

 culus the size of a nut, but soft, urinary organs healthy. 

 And lithotomy is indicated, 1. When the calculus is large 

 and hard. 2. Calculus flat (mural). 3. Calculus large, 

 with vesical catarrh. 4. Two large calculi. 5. One cal- 

 eulus filling the bladder. 



Article X. 



Analyses of Books. 



I.— Philosophical Transactions of the Royal Society of London 

 for 1835, Part II. 



On the Ice formed under peculiar circumstances at the bottom 

 of running water. By the Rev. James Farquharson, of 

 Alford, F. R. S. 



The phenomenon of the formation of ice at the bottom of running 

 water, some years ago, attracted the attention of Knight and M'Kee- 

 ver. M. Arago, in the Annuaire, for 1833, collated the opinions of 

 these writers in reference to the subject, and brought forward a 

 number of additional circumstances from observations made in Ger- 

 many, in order to elucidate its nature. He formed no decided con- 

 clusion, but referred to three circumstances, which were partly ex- 

 planatory of the formation of ice in running water. 1st. The inver- 

 sion by the motion of the current of the hydrostatic order, by which 

 the water of the surface cooled by the colder air, and which, at all 

 points of the temperature of water under 39° F., would, in still 

 water, continue to float on the surface, is mixed with the wanner 

 water below, and thus, the whole body of water to the bottom is 

 cooled alike, by tbe mechanical action of the stream. 2d. The ap- 

 titude to the formation of crystals of ice on the stones, and asperities 

 of the bottom, in the water wholly cooled to 32°, similar to the 

 vol.. in. i- 



