April 2, 1903 



NA TURE 



509 



Hwith ancient civil engineering works, and the remain- 

 ing parts relate to bridge construction, waterworks for 

 cities and towns, railroad engineering, and the Nicar- 

 agua and Panama routes for a ship canal. In the parts 

 relating to modern engineering, the practice and ex- 

 amples described are those followed in America, there- 

 fore for English engineers Prof. Vernon Harcourt's 

 book on " Civil Engineering as Applied in Construc- 

 tion," recently reviewed in Nature, which includes the 

 subjects dealt with in the book now under notice, would 

 be found of more service. 



The first part, relating to ancient civil engin- 

 eering, contains a great deal of interesting inform- 

 ation, but not of a specially original character. 

 The author points out that the science and pro- 

 fession of engineering dates from very early times, 

 and that many large works that would reflect credit 

 on engineers of the present day were executed in the 

 very dawn of history. The anciently populous country 

 at the head of the Persian Gulf was irrigated and made 

 prosperous by a complete system of canals and irriga- 

 tion works carried out in the remote past, and traces 

 of hydraulic works, including dams and regulating 

 appliances, are to be found spread over a large terri- 

 tory in the vicinity of Babylon. From the remains 

 still existing, it is calculated that some of these canals 

 must have been from 25 to 30 feet in depth. It is re- 

 corded that Alexander the Great, when marching 

 through the Assyrian country, found the River Tigris 

 obstructed by masonry dams constructed for irriga- 

 tion purposes. The present Suez Canal was preceded 

 between 3000 and 4000 years ago by a channel cut to 

 connect the Red Sea and the Nile. The extensive 

 hydraulic works for regulating the supply of water 

 from the Nile, some of which were carried out seventy 

 centuries ago, involved engineering work of such 

 magnitude as almost to put the great dam at Assuan 

 recently constructed in the shade. 



The immense blocks of stone used in the construction 

 of the pyramids and temples and for obelisks show that 

 a knowledge of mechanics must have been well devel- 

 oped in very early times. The remains of many of the 

 ancient buildings afford evidence that both round and 

 pointed arches were made use of. Later on the Romans 

 excelled as engineers, whether as bridge builders, road 

 makers, or in works required for sanitation. The 

 Appian Way, constructed more than two thousand years 

 ago, is only one example of the roads constructed by 

 the Romans, both in Italy and in the lands they con- 

 quered, the remains of many of which are to be found at 

 the present day. This road was 350 miles long, and 

 formed a perfect highway between Rome and Brun- 

 dusium. Water supply was another matter in which 

 the Roman engineers excelled, some of the aqueducts 

 along which the water was conveyed for the supply of 

 their towns extending to a length of from 40 to 60 

 miles. The streets of Rome were provided with a 

 complete system of sewers, and building laws were 

 enacted for regulating the thickness of the walls and 

 height of buildings, and the quality of the materials of 

 which they were composed. The harbours at Ostia 

 and those at Tyre and Sidon testify to the knowledge 

 NO. 1744- v OL. 67] 



of the ancients in this department of engineering, and 

 there are bridges still in existence the foundations of 

 which were laid two thousand years ago. 



With regard to the two Isthmian canals, the author 

 sums up their respective capabilities as follows. He 

 considers both routes feasible and practicable ; that 

 neither route has any commercial advantage over the 

 other ; the harbour features may be made adequate for 

 either canal ; the time that will be required for comple- 

 tion is about the same in either case ; the control of 

 the water supply will be simpler in the case of Panama ; 

 the relative seismic conditions in neither case are 

 of sufficient gravity to cause anxiety ; the question of 

 cost is in favour of Panama. 



OUR BOOK SHELF. 



An Account of the Indian Triaxonia, collected by the 

 Royal Indian Marine Survey Ship " Investigator." 

 By Franz Eilhard Schulze. The German Original 

 translated into English by R. von Lendenfeld. 

 (Calcutta : By Order of the Trustees of the Indian 

 Museum, 1902.) 



This admirable report, the latest of the Investigator 

 series, deals with 120 examples of Triaxonid Sponges 

 dredged between the years 18S5-1890, and it is in 

 reality a revised edition of three memoirs contributed 

 by Prof. Schulze during the years 1894-1900 to the 

 Abhandl. Kais. Preuss. Akad., now put into form for 

 translation into English, as modified in respect to im- 

 portant redeterminations arrived at in the study of 

 the Albatross collection, and under the influence of 

 contemporary research. 



A main distinction is drawn between the Amphidisco- 

 phora and the Hexasterophora, the former embracing 

 a description of the Hyalonematidas (four genera, fif- 

 teen species described), the latter of the Euplectellidas 

 (five genera, eight species), Rossellidae (three genera, 

 three species), Farreidas (one genus, one species), and 

 Melittionidas (one genus, three species). Then follow 

 three tables, of which the first gives a list of the 

 Indoceanic Triaxonia known independently of the 

 Investigator, the second a list of the Investigator series, 

 of which there were thirty-one species, eight of them 

 from depths exceeding 1500 fathoms, the third a 

 full classification of the known forms, with stations 

 and localities, twenty-four genera and fifty-four 

 species in all, including records of genera and species 

 of the Asconematidse, Euretidae, Coscinoporidae and 

 Maeandrospongidas of the Challenger and Pola 

 expeditions. 



There are twenty-three magnificent plates, and the 

 forms most noteworthy are Hyaloncma masoni, in 

 which the Palythoa crust is replaced by Cirripedes ; 

 Saccocalyx pedunculata, now removed from the As- 

 conematidae to the Euplectellidae; Lophocalyx spinosa, 

 remarkable for the possession of " silica pearl " 

 spicules ; and Lophophysema inflatum, a much modi- 

 fied Hyalonematid obtained by the Investigator in the 

 Andaman Sea at 498 fathoms, bearing an annular 

 ridge, which sharply subdivides the body into an upper 

 cylindrical portion and a lower conical one, charac- 

 terised by the presence of large irregular cavities be- 

 longing to the inhalant system. 



We congratulate Dr. Alcock and the Trustees of 

 the Indian Museum upon this valuable addition to 

 their reports, which rank high in the literature of 

 marine zooloov. 



