268 



NA TURE 



[July 23, 1896 



river, and clock works are carried out by the (jovern- 

 nient ; the department charged with this work being under 

 the command of a chief engineer, who, with a small 

 staff, has his headquarters at the seat of Government ; 

 the other officers of the corps being stationed throughout 

 the country uhcre\er their presence is required. In the 

 same way the lighthouses, buoys, and sea marks are 

 under the charge of a Government department, the chief 

 of which is the Secretary of the Treasury ; the other 

 members of the Board consisting of two officers of the 

 Navy, two of the Corps of Engineers of the Army, two 

 civilians of scientific attainments, with an officer of the 

 Army and one of the Navy as secretaries. The coast is 

 divided into districts, each under the charge of an 

 engineer. All works in connection with fortifications and 

 defences and military engineering are managed by the 

 department of the Secretary of War. The quarter- 

 master's department takes charge of all stores, transport, 

 and military buildings ; and another officer of the War 

 department has charge of all public buildings and parks. 

 For the guidance of the officers of these several depart- 

 ments a code of regulations is drawn up as to the manage- 

 ment and conduct of contracts, and of works performed by 

 the department. This code provides that " the import- 

 ation and migration of foreigners and aliens under con- 

 tract or agreement to perform labour in the United 

 States is forbidden." That, except in cases of extra- 

 ordinary emergency, the services of labourers and 

 mechanics employed on any public works are limited to 

 eight hours in the day. Legal holidays for employes 

 of the Government are January i, February 22, 

 July 4, and December 25. Day-workmen are paid 

 for these days, and for such other days as may be 

 designated days for national thanksgiving by the. Presi- 

 dent. The first Monday in September, known as 

 " Labors Holiday," is a legal holiday. In the case of con- 

 tracts, all persons tendering are to be notified of the time 

 when the tenders are to be opened, and may be present, 

 either in person or by their agents. Any officer or agent 

 of the Government, or any member of Congress, who 

 receives money or other bribe in connection with any 

 contract or work, is deemed guilty of misdemeanor, and 

 is liable to imprisonment for a period not exceeding two 

 years, and to be fined a sum not exceeding 10,000 dollars. 

 The design of Captain Black's book is to show the 

 prescribed business methods of those of the e.xecutive 

 departments which principally control the Government 

 work, and to describe the nature of the works and the 

 plant and materials most frecjuently required. The general 

 laws and regulations under which all the public works 

 are carried on are given ; also a description of the depart- 

 ments, and of the works executed by them. Engineer- 

 ing principles are not dealt with, but there are numerous 

 descriptions of works, with their cost, and illustrations 

 of the plant used, and the method of carrying them out. 

 These include fortifications, sea and lake shore pro- 

 tection works, river training works, lighthouses, public 

 buildings, &c. 



It is the practice of the Works Department of the 

 Corps of Engineers to issue annually full reports of all 

 works going on in the several departments. These 

 reports are often fully illustrated, and contain numerous 

 details as to contracts entered into, cost of the work, and 

 NO. 1395, VOL 54] 



results attained. Any one who is familiar with these, 

 will at once recognise that the contents of the book 

 are largely taken from them. This, however, ^in) no 

 way detracts from its value. 



Although the book is written for andwould be of great 

 service to engineers in the United .States, it yet contains 

 a great deal of information respecting the works carried 

 out in that country in training and improving rivers ; and 

 the various methods of dredging in use and the cost, and 

 also as to the works for lighting the coast, which would 

 be found useful and instructive to English engineers. 

 " Suction " dredging has been much more largely used in 

 the LTnited States than in this country, whether as applied 

 to the removal of sand or of clay and harder material. 

 The methods used for disintegrating hard material, and 

 either pumping it up by centrifugal pumps or pulsometers, 

 or by a vacuum chamber, is fully described. In the 

 latter case, steam is admitted to a cylinder or vacuuni 

 chamber, then condensed with cold water, the vacuum 

 formed causing an inrush of the materials to be raised 

 through a suction-pipe ; this material is then driven out 

 through the discharge-pipe by the admission of the steam. 

 As an illustration of the nature of the materials this 

 method of dredging is capable of dealing with, it is 

 stated that a 13001b. stone was picked up and forced 

 through the pipes on one occasion, and on another ari 

 iron safe measuring 25 inches by 16 inches by 14 inches. 



OUR BOOK SHELF. 

 Wild Life of Scotland. By J. H. Crawford, F.L.S. 



Pp. 2S0. (London : John Macqueen, 1896.) 

 Pastoral life has charms for a large proportion of the 

 reading public, if one may judge from the quantity of 

 literature dealing with its scenes and events. Perhaps 

 the strain under which men now work in cities, has 

 resulted in a reaction in favour of a return to nature. 

 Certain it is that there is a demand for simple papers on 

 subjects of outdoor natural history ; and though much of 

 the supply to meet is not above criticism, still the taste 

 for descriptions of rural scenes and wild nature is well 

 worth cultivation. Mr. Crawford has a passion for wild 

 nature. He would like to rehabilitate some of the 

 isolated hills and woodlands of Scotland with the rein- 

 deer, beaver, and wild boar ; but the general opinion of 

 his correspondents appears to be : " We cannot afford to 

 grow wood for beavers to gnaw, or for boars to whet 

 their tusks on." To see nature at her best in Scotland, 

 he has gone away beyond enclosures, and has observed 

 and judged of her ways for himself This collection of 

 papers, which represent the result of his observations and 

 meditations, are typical of the forms of life in the woods 

 and waters of Scotland ; they are pleasantly written and 

 attractively illustrated, and will interest all country 

 naturalists. 



A Cosmographical Review of the Universal Law of the 

 Affinities of Atoms. By James Henry Loader. Pp. 93. 

 (London: Chapman and Hall, Ltd., 1896.) 

 It is a little difficult to understand the theory presented 

 in this book. To do justice to the author, and at the 

 same time enable readers of NATURE \.x> appraise the 

 contents at their proper value, we give a few extracts. 

 It is stated that men of science have concluded "that all 

 space must be composed of an clement extremely rarefied, 

 and that element they denominate ether.' 1 laving accepted 

 this opinion himself, the author infers that the ether is 

 " the primary essence of all matter, whether in a gaseous 



