106 



SCIENCE. 



[N. S. Vol. XI. No. 264. 



trasts were instanced. C. H. Hitchcock 

 remarked the inaportance of northern Maine 

 as a place to decide this question, and men- 

 tioned Lake Telos as a promising locality. 

 H. S. Williams again spoke, bringing up 

 the Gasp6 section and mentioning facts 

 about northern Maine. J. M. Clarke also 

 remarked his acquaintance with the De- 

 vonian fossils from Maine and reaffirmed 

 the finality of the organic tests of cor- 

 relation. 



These papers concluded the session of 

 Thursday. In the evening at 7.30 o'clock 

 the Society assembled at the Hotel Raleigh 

 for the annual banquet. To the delight of 

 all present. Professor Emerson was found at 

 the head of the table, and as usual a very 

 merry evening followed. According to the 

 admirable custom, now well established, 

 the fellows brought their wives, and the la- 

 dies gave a brilliant aspect to the dinner. 

 Ninety -five covers were laid, including 

 about 15 for ladies. 



J. F. Kemp. 



Columbia University. 



SCIENTIFIC BOOKS. 

 Fronfinus and the Water Supply of the City of 



Borne. By Clemens Heeschel, Hydraulic 



Engineer. Boston, Dana Estes & Co. 1899. 



4to. xlix + 296 pages. 



Frontinus was appointed water commissioner 

 of Rome in 97 A.D., and soon thereafter wrote 

 his two books, generallj' called De Aquis, ou its 

 waterworks. The sole original Latin manu- 

 script, dating from the twelfth or thirteenth 

 century, is preserved in the library of a Bene- 

 dictine monastery in Italy, and the photographic 

 reproductions of its twenty-four pages which Mr. 

 Herschel gives will be of interest to classical 

 scholars. He also gives the Latin text and its 

 English translation on facing pages, and adds 

 twelve chapters of explanatory and critical mat- 

 ter which are of special value to civil engineers 

 and arehseologists ; these are accompanied by 

 eighty-four illustrations and three folding 

 plates. This is the first time that De Aquis 

 has appeared in English translation, and it is 



safe to say that no single volume has ever been 

 published that contains such a wealth of in- 

 formation ou the water supply of ancient Rome. 



The treatise of Frontinus begins with a 

 description of the nine aqueducts erected 

 prior to 97 A.D., mentioning their builders, 

 sources and lengths. The subject of water 

 measurement is next discussed and the sizes of 

 the standard pipes are given, this being pre- 

 paratory to determining the amount of water 

 furnished by each aqueduct and how much was 

 used for fountains, for public buildings and for 

 private uses. Then the quality of the waters 

 and the laws for the prevention of pollution 

 receive attention, and this is followed by a 

 statement of the duties and powers of the 

 water commissioners, and of the regulations 

 for preventing the unlawful use of water. 

 Lastly, the methods of repairing the aqueducts 

 are discussed, and the laws for ensuring their 

 proper maintenance are given. 



Mr. Herschel discusses at length the engi- 

 neering and hydraulic features of the aqueducts 

 and of the methods of distributing the water. 

 It is clearly shown that the Roman engineers 

 had no rational methods of measuring water, 

 such quantities as cubic feet per second or gal- 

 lons per hour being beyond their powers of con- 

 ception. The unit of measurement used by them 

 was called a ' quinaria,' this being originally 

 a circular pipe whose diameter was IJ Roman 

 digits, later the number of square units in the 

 cross-section of this circle, and later the quan- 

 tity of water passing through this area. Evi- 

 dently it was understood that the discharge 

 through a pipe or channel would vary with the 

 velocity, as Frontinus says that the aqueduct 

 Virgo could not be properly measured near its 

 source, where the current was too slow, but 

 near the city where the velocity was greater he 

 found it to give 2504 quinarias. In general, 

 however, the measurement of water was made 

 by finding the area, in quinarias, of the cross- 

 section of the channel or pipe ; thus a denaria 

 pipe, whose diameter was double that of the 

 quinaria pipe, was supposed to discharge four 

 quinarias of water. 



The statement is commonly made in cyclo- 

 pedias that the aqueducts of ancient Rome de- 

 livered about 300 gallons of water per day for, 



