February 8, 1889.] 



SCIENCE. 



roi 



behind men with the beam of light on a target, very good practice 

 can be made, so long as the men are in the beam, the sights of the 

 guns then being illuminated ; if, however, the men are out of the 

 beam, and consequently invisible, the accuracy of the practice is 

 much reduced. 



The Axo Battery. — The most widely used galvanic cell for 

 " open-circuit " work — that is, for bells, burglar-alarms, telephones, 

 etc., where^the current is only taken out for short times — is the Le- 

 clanche, or some of its modifications. The cell has many advantages : 

 it needs very little attention, its electro-motive force is comparatively 

 high, there is no eating-away of the zinc when the cell is not working. 

 The only troubles have been in the evaporation of the liquid, the creep- 

 ing of the solution over the edges of the jar, and the corrosion of the 



binding-post contact at the carbon pole. These defects are rem- 

 edied in the new Axo type of Leclanche cell shown by the illustra- 

 tions. Here the porous cup forms of itself the cover of the cell, 

 which is hermetically sealed by pouring wax or paraffine in the 

 space between the top of the cup and the edge of the jar. As the 

 depolarization of the battery requires that there be a certain amount 

 of ventilation, this is secured by deep grooves in the sides of the 

 carbon, coming above the cover of the jar. It will be seen that 

 the zinc passes through a separate hole in the side of the jar, which 

 is closed by a rubber stopper. The connection with the carbon is 

 made by a patented metallic clamp and thumb-screw, shown in 

 the figure. Taken altogether, the Axo is an advance in galvanic 

 cells. It can be sealed and left to itself, until, as must finally hap- 

 pen in every battery, the zinc and .solution have to be replaced, 

 when with very little trouble it can be practically renewed. For 

 ordinary bell-work it would probably last a year or more without 

 attention. 



NOTES AND NEWS. 



Professor Shaler of Harvard has returned from his tour of 

 geological exploration through the Dismal Swamp. 



— The Rev. Dr. George E. Reed, pastor of the Trinity Methodist 

 Church of New Haven, is now at work upon his letter of acceptance 

 as president of Dickinson College of Carlisle, Penn. 



— Mr. F. Kiistner has made a very interesting series of observa- 

 tions on the aberration of fixed stars, and, from certain discrepan- 

 cies between early observations made by Struve and recent ones 

 made by himself, arrives at the conclusion that the altitude of the 

 pole, which is assumed to be a constant in the formula applied, is 

 in fact variable. He found that in the fall of 1S84, at Berlin, the 

 polar altitude must have been 0.2" greater than before and after that 

 season. As this result appeared somewhat startling, he subjected 

 other observations made at Pulkowa and Gotha to a thorough in- 

 vestigation, which proved the correctness of his view. Mr. Kiistner 



attributes these variations to meteorological and hydrological phe- 

 nomena which are caused by the action of the sun. Helmert's in- 

 vestigations tended to show that these irregular movements of mat- 

 termight result in changes of latitude not exceeding a few hundredths 

 of a second, while William Thomson concluded that these changes 

 might be as great as half a second. From Kiistner's observations, 

 it appears that the real changes are intermediate between these two 

 values. 



— Professor Hill of the School of Geology of the University of 

 Texas plans the establishment at the university of an educational 

 museum which will represent in the broadest sense the geologic 

 conditions — structural, economic, organic, and general — of the 

 earth, and to illustrate these features as far as possible by Texas 

 material accompanied by maps, models, and labels. This museuin 

 will exhibit not merely the extraordinary, but also the far more im- 

 portant and too little valued ordinary features of that State ; so that 

 any person, citizen or stranger, will find compactly arranged in the 

 halls of the university a complete and instructive synoptical exhibit 

 of all the diverse natural features of Texas. The museum will also 

 be a medium of exchange with similar institutions outside the 

 State. The attention which will be attracted abroad by properly 

 prepared and representative specimens from Texas, conveying 

 clear and accurate scientific informati -a 'hat can be disseminated 

 in no other manner, will attract the earnest interest of a class of 

 intelligent people who cannot be otherwise reached. The functions 

 of the museum will also be distributive as well as collective, and 

 its utility not confined to the university building, but disseminated 

 throughout the State, it being the intention to select from its dupli- 

 cates typical educational series for distribution to high schools con- 

 nected with the university wherein the natural sciences are taught. 



— A movement has been started in Norway, says Nature, for 

 the despatch in the summer of 1S90 of an expedition which will try 

 to reach the north pole, and it is proposed that the leadership shall 

 be offered to Dr. Nansen. Those who are arranging the plans main- 

 tain that no other country could furnish such a crew of experienced 

 and hardy ice- men and arctic travellers as Norway, and that a 

 winter or two in the arctic regions would affect these men very 

 little. The intention is that an attempt shall be made to reach 

 the pole by way of Franz Josefs Land, — a route advocated by 

 the most experienced Norwegian arctic travellers as well as by 

 several well-known men of science who have studied the problem. 

 Ski, which have played such a prominent part in the Norden- 

 skiold and Nansen Greenland expeditions, would no doubt again 

 be of great service. 



— The board of overseers of Harvard College, at a meeting held 

 Jan 30, adopted, after prolonged dicussion, the following vote : 

 " Voted, that, in the opinion of this board, it is expedient that every 

 undergraduate be requested to report in person early every morn- 

 ing, with a moderate and fixed allowance for occasional absences ; 

 that attendance at the exercises of each course be more rigidly en- 

 forced ; that the system of advisers, somewhat as applied to special 

 students, be extended to the freshman class ; that the reports of 

 the presence and absence of students be collected daily by monitors, 

 and daily entered on the books ; that no choice of studies made by 

 a student be valid if it calls for more than three lectures or recita- 

 tions on any day of the week, unless the choice has been specially 

 allowed by the dean ; that, in order to make it more difficult for 

 students to prepare by a brief period of cramming to meet the tests 

 applied, the faculty require all the instructors to provide tests of the 

 progress of their students with sufficient frequency to enable them 

 to enforce effectively Section 7 of the Regulations ; that admonition 

 be administered by the dean on his sole authority, and that the powers 

 of that officer be so enlarged, at whatever increased expense it may 

 be necessary to incur, that the records of attendance may always be 

 ready for inspection by the proper officers ; that the faculty be 

 asked to prepare and report a series of rules, which, in their judg- 

 ment, will give practical effect to these recommendations." This 

 was adopted by a vote of 16 yeas to 4 nays, those voting in the 

 negative being President Eliot, Dr. Phillips Brooks, Dr. Walcot, 

 and Charles R. Codman. The carrying-out of these recommenda- 

 tions will depend on the faculty, which, it is understood, are opposed 

 to their spirit. 



