ARTILLERY AND EXPLOSIVES. Essays and Lectures Written and Delivered at Various Times. By Sir Andrew No ble, Bart., K.C.B., D.Sc. (Oxon.), D.C.L., F.R.S., etc. New York: E. P. Dutton Company, 1907. 8vo.; pp. 548. Price, $6. Although this work is a compilation of vari ous notable essays and lectures delivered by the author, the fact that they are arranged in chronological order, and that each represents the progress in artillery and explosives at the date the papers were given, makes the work thoroughly connected and complete, with noth ing of the fragmentary character which might at first be supposed. Sir Andrew Noble's repu tation as one of the first authorities in the world on the subjects dealt with, would alone give great value to the work ; but judged strictly on its own merits, the present volume is one of the most lucid, complete, and truly interesting works on the subject that has ap peared for many years. It opens with a paper read before the Royal Artillery Institution in 1858 on the "Application of the Theory of Probabilities to Artillery Practice," and closes with a paper on "Methods That Have Been Adopted for Measuring Pressures in the Bores of Guns," read before the British Association in 1894. Hence the book covers the most progressive period in the development of ar tillery ; in fact, it may be said to embrace the whole of the time during which the mod ern high-velocity rifle gun has been brought to its present excellence. The particular value of the book arises from the fact that it em bodies the results of valuable experimental work carried out largely by the distinguished author himself. Furthermore, these experi ments were favored by the fact that ample means were at command for work which is necessarily of an intricate and costly charac ter. Notable chapters are those on "Tension of Fired Gunpowder" ; "Researches on Ex plosives" ; "Heat Action of Explosives" ; "The Energy Absorbed by Friction in the Bores of Rifle Guns" ; and "Pressures Developed by Some New Explosives." The work is freely illustrated with diagrams and woodcuts, and is enriched with elaborate tables. At the close of the book are a set of full-page drawings, showing the turret and other mountings of heavy ordnance on ships of the British navy. THE SANITARY EVOLUTION OP LONDON. By Henry Jephson, L.C.C. Brooklyn: The A. Wessels Company. 8vo. ; cloth; 440 pages. Price, $1.80 net. The story of the modernization of London reads like a romance. Sixty years ago London was a medieval city, in a sanitary condition scarce conceivable to a modern mind. The elements of decency and sanitation were ne-gleeted—almost unknown. The sewers were open ditches draining directly into the Thames, whose polluted tidal waters swinging slowly back and forth every twelve hours provided the drinking water of a large part of the popula tion. The rich drained into cesspools beneath their houses ; in the poor districts drainage and sanitation were unknown. Water supply was doubtful in quality, intermittent in supply, and not laid into the houses. Thousands of families lived in single rooms—hundreds of single rooms harbored two or more families— and infectious disease was chronic in many houses. Attempts to improve conditions have been steadily fought by vested interests. Conces sion after concession has been wrung from Parliament, placing powers in the hands of the people, and responsibilities on the shoul ders of property owners. When the party of progress found the opposition too strong for them, they merely waited until an extra wave of cholera or smallpox raised public indigna tion and gave them the support they needed. Finally, in 1888 the London County Council was formed. For the first time a central body took hold of the work of government, for until then innumerable small bodies had ruled and wrangled, each supreme in one tiny corner of London. With the creation of the County Council, ratepayers for the first time were able to elect their own representatives and to hold them to an accounting. The author is a member of the London County Council, and like so many members of that unsalaried organization, has thrown himself whole-heartedly into the task of thor oughly mastering the subjects he is called on to handle. He marshals his facts lucidly and concisely, and has given us a book which can not be overlooked by anyone interested in the problem of city government. MATHEMATICAL GEOGRAPHY. By Willis E. Johnson. New York: American Book Company. 12mo.; cloth; 336 pages, illustrated. Price, $1.10. Even descriptive geography is extremely fas cinating, for it possesses an intimate personal element. When we go to the study of the re lations of our earth to the rest of the universe, the personal element still remains, but there is added a feeling of grandeur. The books treating of the astronomical relations of the earth with reference to their practical useful ness have not been satisfactory in the past. They were either too puerile or too deep ; too limited or too scattered ; so that the casual investigator was not attracted to the consider ation of these most useful questions. "Mathe matical Geography," by Mr. Johnson, meets the needs of the interested layman by treating of file mechanical phenomena exhibited by our globe. Tlie computation of time, latitude, and longitude are all clearly taken up and care fully explained. The principals of map-mak ing, and the various kinds of projections—-Mercator's, homolographic, and conic—are fully gone into, as are the rotation and revolution of the earth and the "nutation" of the poles. In the appendix are instructions for the con struction and adjustment of sun-dials. The entire work is interesting as well as practical. INDUSTRIAL ALCOHOL. The Production and Use of Alcohol for Industrial Purposes and for Use as an Illum inant and as a Source of Motive Power. By John Geddes Mcintosh. With 75 illustrations and 25 tables. London: Scott, Greenwood Co. New York: D. Van Nostrand Com pany. 8vo.; cloth; 252 pages. Price, $3. When our Denatured Alcohol Bill was under discussion, it seemed that an unlimited field of wealth was about to be opened to all of us. To become enormously wealthy, all one had to do was to set up a still, and convert into alcohol the disagreeable refuse that the garbage man formerly carted away. However, when the distilling of alcohol was shown by those conversant with the subject to entail too great an initial outlay for the individual to profitably carry it on, the subject was dropped, and now we hear nothing more about it. In spite of this quite usual treatment, our law has made possible an industry that in other coun tries has proved to be full of profit to those who intelligently carry it on. The knowledge necessary to operate such a plant is not too technical to be beyond the reach of any intelli gent man with some scientific aptitude, nor is the capital needed for its installation excessive. Like every business, however, such operations must be begun and managed with intelligence. A number of books on the subject have been written in foreign tongues, but in English a much smaller number. Among th'e best of these may be mentioned those by J. R. Brachvogel and J. G. Mcintosh, respectively. Mr. Brach-vogel's work is larger and more complete than any of the others that have appeared. Mr. Mcintosh's book is less comprehensive, but seems to be very complete and to cover about as much ground as is necessary. He treats of the properties of alcohol, the various ways of distilling, and the different materials used in its production, such as beets, grain, pota toes, and so on. In ending he discusses the alcohol derivatives and the use of alcohol for lighting purposes. HANDBOOK OP AMERICAN GAS ENGINEER ING PRACTICE. By M. Nisbet-Latta. New York: D. Van Nostrand Com pany. 8vo.; cloth; 466 pages. Price, $4.50 net. The author intends this to be the first of a series of handbooks on gas engineering, which when complete will cover every branch of the industry. He goes at length into the manufac ture of water gas, and the distribution of gas ; and 200 pages are devoted to general tech nical data. The book is written for the prac tical man, and should prove of use to those employed in gas works. Methods of manu facture of gas other than water gas will be described in subsequent volumes, but the parts of this book dealing with distribution and gen eral data are applicable to all fields of gas en gineering. THE STOKER'S CATECHISM. By W. J. Con nor. New York: Spon Chamber lain. 16mo.; paper; 63 pages. Price, 50 cents. The man about to become a stoker is under the disadvantage of being unable to find any textbooks on the subject. If he is unable to find some veteran who is sufficiently kindly to instruct a novice, he must gain his knowledge by experience at the risk of being discharged by his employer. The "Stoker's Catechism" has a number of questions and answers intend ed to prevent the more important of the mis takes that beginners are apt to make. Mr. Connor the author, is in error when he places the value of the horse-power at 32,000 foot pounds per minute. This slight oversight, however, does not in any way detract from the usefulness of what should prove to be an excellent guide to its subject. DRAHTLOSE TELEPHONIE. Ernest Ruhmer. Berlin: The author, 1907. paper; 6% ? 11 inches; 142 pages, 139 fig ures. Price, $1. A fully-illustrated and complete description of the progress of wireless telephony. MODEL STEAM ENGINE DESIGN. By R. M. de Vignier. New York: Spon Chamberlain. Paper; 95 pages; il lustrated with diagrams. Price, 25 cents. A little handbook containing practical in formation and calculations of use to model engineers. METRIC WEIGHTS WITH ENGLISH EQUIVA LENTS. By Hugh P. McCartney. New York: Spon Chamberlain, 1907. Red leather; 3y2 x 4 inches, 88 pages. Price, 50 cents. A convenient set of tables showing the values of the metric weights from 1 gramme to 50,000 kilogrammes in the English and troy systems. The calculations are based on the gramme-value of 15.432 grains.