April 27, 1917] 



SCIENCE 



413 



Practise in deep water work. Outline of nature 

 of problems in close to bottom wire drag surveys. 

 Surface observation insufficient. Analysis of ac- 

 tion of wire in striking an obstruction with ob- 

 served phenomena. Geological phase. Experi- 

 ments and conclusions. 



Estimate of value of method and results. Im- 

 provements in apparatus and instruments. Stand- 

 ardization of measurements. Definite recognition 

 of need for experiment and research in all branches 

 will lead to continuous improvement in results. 

 The Engineer and the Newspaper : Henkt A. Wise 



Wood. 



Herein Mr. Wood first recounts the origin of the 

 practise of engineering science as a civilian occu- 

 pation. He then describes the slow development in 

 printing during the first eighteen centuries, com- 

 mencing with the manufacture of paper, and re- 

 lates to the improvements as they took place up to 

 the nineteenth century, when the engineer took the 

 art in hand, transforming it from a hand-worked 

 to an automatic basis. Mr. Wood then dwells on 

 the more extensive improvements made in printing 

 during the nineteenth century, particularly in the 

 printing press. 



Having brought the press to its present state of 

 perfection, he enumerates the other improvements 

 in printing. In connection with the composing 

 room he expounds the revolutionary advantages of 

 the linotype, and in disclosing the improvements 

 made in the stereotyping room he explains the 

 processes which transformed it from a hand-worked 

 into an automatically-operated department — ^the 

 autoplate, introduced early in the twentieth cen- 

 tury, being the principal factor. 



Mr. Wood then passes on to the newspaper's 

 latest achievement, the stereotyper 's dry matrix, 

 with which the history of printirig ends. And he 

 closes with a prophecy that the next step forward 

 in printing will be taken in the printing-press de- 

 partment. 



Independent Laboratories in the Engineering In- 

 dustries: Clayton H. Sharp. 

 The university is the proper place for pure sci- 

 entific work; that is, work done without any com- 

 mercial motive. The large manufacturing organi- 

 zations have recognized the importance of indus- 

 trial laboratory work and many of them have or- 

 ganized extensive laboratories for their own pur- 

 poses. The small manufacturer, being unable to es- 

 tablish an efficient laboratory of his own, may take 

 his work either to a technical school or to an inde- 

 pendent industrial laboratory. The technical 

 school is, however, unsuited for many classes of in- 



dustrial work through limitations of equipment 

 and because, being organized for purposes of edu- 

 cation, industrial work does not fit properly into 

 its scope. The best solution of the laboratory 

 problem of the small manufacturer is recourse to 

 independent laboratories, adequately manned and 

 equipped and supported by the work which they 

 do. Such laboratories may olfer facilities quite 

 comparable with those of the laboratories of the 

 great corporations and should, if adequately sup- 

 ported, prove an important factor in industrial 

 progress. 



A Study of the Relation between Tension and Mag- 

 netic Permeability : James T. Rood. 

 Magnetic curves are commonly assumed to hold 

 irrespective of conditions under which material is 

 to be used. Is this correct? 



Does tension effect permeability of magnetic ma- 

 terials 1 



Does this change with material? 

 What is the magnitude of this change? 

 Tests on cast iron showed permeability unaf- 

 fected by tension. 



Tests on wrought iron showed permeability con- 

 siderably affected by tension. To top of knee of 

 B-S curve, tension below a certain amount in- 

 creased permeability, greater tensions decreased 

 permeability. Above knee, all tensions up to 

 elastic limit decreased permeability. Higher the 

 stress, the greater the percentage decrease; higher 

 the degree of saturation, the less the percentage 

 decrease. 



Tests on steel showed permeability to be af- 

 fected in the same manner as wrought iron. 



With these materials the increase and decrease 

 in permeability may be as high as 20 per cent. 



Eifect seems to increase as elasticity of material 

 decreases, but cast iron is an exception. 



The presence of carbon may be a determining 

 factor. 



Notes on the Theory of the Air Core Auto-trans- 

 former: Walter L. Upson. 



The theory of the auto-transformer, especially 

 tha non-ferric type, is worked out by the method of 

 complex quantities. It is pointed out that the re- 

 sistances and leakage reactances of air-core trans- 

 formers being constant and the magnetizing cur- 

 rent being directly proportional to the impressed 

 voltage, the characteristic performance is entirely 

 dependent on the voltage and when known for one 

 value of voltage may be immediately found for any 

 other voltage. 



A brief discussion of the peculiar characteris- 

 tics of this apparatus is indicated by theory is 



