558 



NATURE 



[September 22, 1910 



In place, therefore, of foreign species, with which 

 it seems impossible for the ancient Egyptians and 

 Assyrians to iiave been acquainted, it seems to me 

 that all the ruminants referred to by Dr. Keller are 

 local forms, well known to the artists and sculptors 

 bv whom they were painted or chiselled. The same 

 remark will, I believe, apply to the representations 

 of the Indian elephant, like the one on the obelisk of 

 Salmanassar IT. (Fig. 130, p. 375), although the author 

 regards these animals as of foreign origin. He ap- 

 pears, however, to be unacquainted with the definite 

 record that at an early date the Assyrian kings hunted 

 the Indian elephant jn the Euphrates valley, this 

 record being confirmed by the occurrence of fossilised 

 remains of the so-called Elef'has armeuiacns, which 

 mav have been merely a local race of the former 

 species, in Armenia. 



The Indian elephant being thus shown to have been 

 a local, instead of an imported, species in ancient 

 Assyria, it may be suggested that if the unicorn 

 animal on the obelisk of Salmanassar ii. be, as Dr. 

 Keller suggests (p. 386, Fig. 133), the Indian Rhino- 

 ceros unicornis, which is known to have had formerly 

 a much wider distribution than at the present day, 

 that species may likewise have ranged in Assyrian 

 times into Mesopotamia; and, if this be the case, it 

 will be practically certain that all the animals repre- 

 sented by the artists of ancient Egvpt and .Assyria 

 were more or less local species. 



More criticism of much the same nature might be 

 added, but sufificient has been stated to show that 

 while the volume under review contains a very large 

 amount of valuable information concerning the early 

 history of well-known animals, at least the portion 

 relating to ungulates stands in need of revision by a 

 writer with a fuller knowledge of that group than 

 the author appears to possess. R. L. 



THE DESIGN OF REINFORCED CONCRETE 

 STRUCTURE. 



(i) .4 Concise Treatise on Reinforced Concrete. By 

 C. F. Marsh. Pp. viii -1-225. (London: Constable 

 and Co., Ltd., 1909.) Price 7.5. 6rf. net. 



(2) Concrete-Steel Construction. By Prof. Emil 

 Morsch. /Vuthorised translation from the third 

 (1908) German edition, revised and enlarged by 

 E. P. Goodrich. Pp. i.^ -1-368. (New York: The 

 Engineering News Publishing Co. ; London : 

 Messrs. Constable and Co., Ltd., 1909.) Price 21*. 

 net. 



(3) // Cemento Armato e la sua afiplicazione practica. 

 By Cesare Presenti. Pp. 141. (Milan : Ulrico 

 Hoepli, iqio.) 



(4) Le prove dei niateriali da costruzione c le costru- 

 zioni in Cemento Armato. By Giulio Revere. Pp. 

 .\ii + 54i. (Milan: Ulrico Hoepli, 1910.) Price 

 II lire. 



'T~"HE employment of reinforced concrete in connec- 

 J- tion with engineering and architectural struc- 

 tures has now become so general that a text-book on 

 somewhat simpler and more condensed lines than 

 -\"0. 2134, VOL. 84] 



those of Mr. Marsh's well-known treatise on "Re- 

 inforced Concrete ' will be gladly welcomed by many 

 engineers and architects. The present volume (i) 

 has been, to a certain extent, based upon a series of 

 lectures delivered by the author in the winter of 1908-9 

 at the Central Technical College, London ; hence, in 

 all cases the derivation of important formulfe has been 

 fully dealt with, but lengthy and detailed descriptions 

 of the various systems of construction have been 

 omitted ; this latter portion of the subject was fully 

 dealt with in the author's manual. 



The first two chapters deal respectively with the 

 properties and the behaviour under bending of rein- 

 forced concrete, the important question as to the value 

 of the modulus of elasticity (Ec) for the concrete which 

 should be adopted in the calculations required in con- 

 nection with the design of struts and beams is very 

 fully discussed, and Mr. Marsh shows that we may 

 safely assume it to be 2,000,000 pounds per square 

 inch when the concrete is two or three months old, 

 or, in other words, that the ratio of E,/Ec may be 

 taken as 15. In the third chapter the various 

 assumptions which have to be made for purposes of 

 calculation are briefly explained, and their validity 

 discussed ; it is shown that, when calculations are 

 based on the safe working stress for concrete, it is 

 sufficiently accurate for all purposes to assume a 

 straight line stress-strain relation for the concrete as 

 well as for the steel. 



The rest of the book is devoted to methods of cal- 

 culation ; after a short discussion of the bending 

 moments of beams and slabs partially built in at the 

 supports, direct compression is taken up, and then the 

 longitudinal, bond, and shearing stresses in rect- 

 angular section and T section beams with single or 

 double reinforcement ; pipes and similar structures 

 subjected to either internal or external pressure are 

 then dealt with ; a very thorough and complete in- 

 vestigation is next given of the calculations which 

 are necessary in the design of small, and large, span 

 arches, and other pieces which are subjected to both 

 direct stresses and to bending stresses. The design 

 of reinforced concrete arches is always admittedly a 

 difficult piece of work, and there is no doubt that 

 the treatment which Mr. Marsh gives of this branch 

 of reinforced concrete work will prove of great service 

 to those who only occasionally have to deal with such 

 structures, as the methods explained and discussed 

 are simple and direct. 



In the last chapter a brief description is given of 

 the general methods of reinforcement which should 

 be adopted in structural work. 



Mr. Marsh, by his well-known treatise, established 

 his position as a trustworthy guide in this i.mportanl 

 field of engineering and architectural design, and the 

 present volume is quite worthy of the reputation thus 

 acquired. 



(2) Prof. Morsch, in his capacity as director of the 

 technical bureau of the well-known firm of Wayss 

 and Freytag, has been responsible for the design and 

 erection of the reinforced structures built by this 

 firm during the past fifteen years ; he has, therefore, in 



