^une 5, 1879] 



NATURE 



127 



tary emerilus. By his tact and energy at the time of 

 change of government at Rome, he was enabled to save 

 the Archives of the Academy, of which during his lifetime 

 he was one of the most active members. 



Volpicelli was well known abroad, and the Emperor of 

 Brazil when in Rome spent some time with the professor, 

 and conferred upon him the grade of officer of the 

 Imperial Order of the Rose. Volpicelli travelled much, 

 and in 1850 he made a long stay in England, where he 

 made the acquaintance of Faraday, Brewster, Airy, Mur- 

 chison, Sabine, Panizzi, Wheatstone, and others, with 

 whom he afterwards continued to correspond. In France 

 and Switzerland also, he was the friend of the most 

 eminent men of science. 



Volpicelli was an energetic worker in his favourite 

 field of electrical research, and to the last maintained 

 with vigour the theory of Melloni, at which he had 

 worked for twenty years. The papers and other works 

 published by Volpicelli were very numerous ; no less than 

 270 are enumerated in a list published by the Academy 

 dei Lincei. Although he is chiefly known by his re- 

 searches in electricity, these papers show that he did 

 tnuch other work in various departments of mathematics 

 and physics. Volpicelli's papers will be found mainly in 

 the Atii de PAccadetnia dei Lincei, and the Comptes 

 Rendus of the Paris Academy. Very few of them have, 

 however, been translated into English, a circumstance 

 which must be regretted for the sake of English scientific 

 men, to many of whom Volpicelli's researches are known 

 only by name. He died calmly on April 14, having been 

 visited shortly before his death by the Pope's brother, 

 Cardinal Pecci. 



AN AMERICAN SUGGESTION 



■XXTE have occasionally noted in these columns the 

 ' " formation of mathematical societies, and we have 

 ventured, in our ignorance, to suggest that as a conse- 

 quence of the great advance in the cultivation of mathe- 

 matics recently made by our American cousins, the time 

 had come for the formation of an American or (following 

 the analogy of associations nearer home) of a Baltimore 

 Mathematical Society. 



A short account of the Proceedings at the fifth meeting 

 of the Lehigh Mathematical Society — recorded in the 

 Bethlehem Daily Times (Pa.) for March 17 — may interest 

 kindred societies on this side the Atlantic, and serve to 

 show that the transactions of such learned bodies may 

 contain " something of importance and profitable {sic) to 

 the general reader.' ' 



It appears that in order to remedy the defects in the art 

 of surveying, it has been made imperative (so says Mr. 

 S. R. Vay, Civil Engineer, the reader of the paper') by 

 the American legislature that " each county should at its 

 own expense and on its own land, plant, or erect, two 

 monuments of stone, so that the straight line between 

 them should be an exact and due meridian, or north and 

 south line ; in order that thereby surveyors, by setting a 

 compass on the one monument, and pointing it to the 

 other, might readily ascertain the deviation or variation 

 of the magnetic needle, and thus be prevented from 

 committing errors in the determination of property lines 

 and landmarks." His soul was much stirred at the 

 neglect of this "scientific duty." It seemed to him that 

 ■"the scientists of the valley ought to urge, with noun- 

 certain voice, the erection of such or similar monuments. 

 With but little extra expense they could easily be made 

 to interest and to educate, as well as to serve the purpose 

 designed by the legislature. Imagine, for instance, two 

 beautiful granite monuments standing in appropriate 



* Touching fir.>t upon the necessity of preserving boundaries and upon the 

 methods employed by the ancients ; tracing the word geometry to its source, 

 and relating how the Egyptians were puzzled to find their landmarks, he then 

 j>assed on to the discovery of the magnetic needle, and the perplexity caused 

 »0 country surveyors by tne deflection of the same. 



situations on the spacious ground of Lehigh University, 

 one mounted with a sun-dial, and the other with an ane- 

 mometer. On one of them should be cut in plain letters 

 the latitude, longitude, and elevation above the sea of 

 that exact spot. On the other should be recorded a 

 statement of the mean annual temperature and rainfall 

 of the valley. The axis of the sun-dial would not only point 

 to the steadfast pole, but be parallel to the earth's axis ; it 

 could, indeed, be furnished with a hoop or circle, to re- 

 present the equator, and with others to represent the 

 meridians of Greenwich, Washington, and Bethlehem ; a 

 circle to indicate the ecliptic would not be difficult to add, 

 which, by properly constructed clock-work should be 

 always kept parallel to the real ecliptic itself. Thus all 

 who might pass that way would be interested in reading 

 the inscriptions and observing the time, and many would 

 be instructed in the science of astronomy. Even to 

 students it would be of benefit in lightening their mental 

 struggles to grasp, conceive, and understand the idea of 

 the ecliptic circle and the ecliptic plane." 



In the discussion which followed, the President doubted 

 the wisdom of the legislature, and thought the better way 

 would be to require higher qualifications from surveyors. 



Dr. H. E. Licks inquired the expense of such a sun-dial 

 as Mr. Vay had described. 



Mr. A. S. Tronomy said " it was usual to consider the 

 ecliptic as a fixed plane when illustrating the yearly 

 motion of the earth. When considering the daily rotation, 

 however, he could see that Mr. Vay's plan had some 

 advantage." 



The next paper was by Prof. Ternion, " On the conse- 

 quences which would result from denying or reversing the 

 tenth axiom of Euclid." The argument, we learn, was 

 "elaborate and profound, being exemplified by long 

 formulas written on the blackboard." He showed that 

 "if the properties of matter or space were such that the 

 axiom became false, a knot could not be tied in a string, 

 that a hollow rubber ball could be turned inside out with- 

 out tearing or stretching, and that no satisfactory system 

 of paper or silver money could be employed." 



Mr. K. M. Puter considered the paper as an example of 

 mathematical analysis, one of very great value, but he 

 considered it fortunate that we cannot practically reverse 

 the axioms of geometry. " If we could, the results would 

 be disastrous." Our notice of the Proceedings at this 

 interesting meeting have extended to some length, but 

 they may be suggestive of matter for societies on this side 

 of the world. We cannot close, without alluding to 

 another feature, and that is the subsequent proceedings 

 (unscientific) before the members separated. 



Crackers and cheese were brought forward and the 

 knot untied by the Secretary " without denying any axiom 

 whatever." " The mathematical joke and the hearty 

 laugh were heard," and, tell it not in Gath, they sang a 

 song. Of a Mathematical Society not a hundred miles oflT, 

 the first President wrote, " not a drop of liquor is seen at 

 our meetings, except a decanter of water ; all our heavy 

 is a fermentation of symbols ; and we do not draw it 

 mild. There is no penny fine for reticence or occult 

 science ; and as to a song ! not the ghost of a chance." 



THE STANDING STONES OF CALLANISH 



THE object of the present paper is to describe the 

 standing stones of Callanish, Island of Lewis, ac- 

 companied by notes of such measurements as the author 

 was able to take during a somewhat hurried visit to these 

 very interesting memorials of the early inhabitants of our 

 islands. 



Leaving the town of Stornoway, we soon find ourselves 

 amongst great tracts of moorland, with sheets of water 

 large and small on all sides. The deep black peat is 

 being cut and piled up into stacks, when, after being dried, 

 it will serve for the winter's fuel. The peats in the Lewis 



