October 22, 1886.] 



SCIEJS'CE. 



365 



will be found a very convenient book of reference 

 by those who have already had some acquaintance 

 with the methods of determining the constants of 

 terrestrial magnetism, and who desire to refresh 

 their memories upon any of the more important 

 principles of the theory and practice of the instru- 

 ments ordinarily used in magnetic surveys. Such 

 persons will find especially convenient the forms 

 given for recording and reducing observations 

 made with the various instruments. Some trouble 

 would be saved, however, if the explanations of 

 the quantities set down in each column were 

 brought into a closer connection with the columns 

 themselves. To those unacquainted with the sub- 

 ject the book will often seem wanting in clear- 

 ness, — a fault which appears in many cases to be 

 the I'esult of too great an effort at condensation. 

 A few pages are devoted to the method of least 

 squares, and tables are given to assist in determin- 

 ing the meridian from observations on the elonga- 

 tion of Polaris. Opinions will differ as to the 

 advisability of inserting so much of a general dis- 

 cussion on the relations between systems of units 

 in order to derive the ratio of the ■ foot-grain ' to 

 the C. G. S. value of the horizontal intensity. 



— Mr. A. Lawrence Rotch, of the Blue Hill 

 meteorological observatory, has issued reprints of 

 several articles in the American meteorological 

 journal, with additional heliotype illustrations, on 

 the ' Mountain meteorological stations of Europe,' 

 which he visited in the summer of 1885. The 

 establishment, outfit, publications, and results of 

 seven stations are described in much detail. Then- 

 names, altitudes, and dates of establishment are 

 as follows : the Brocken, Germany, 1,141 metres ; 

 Schneekoppe, Germany, 1,599 metres, 1880 ; Wen- 

 delstein, Bavaria, 1,837 metres, 1883 ; Hoch Obir, 

 Austria, 2,148 metres, 1878 ; Sentis, Switzerland, 

 2,504 metres, 1882 ; Pay de Dome, France, 1,463 

 metres, 1876 ; Pic du Midi, France, 2,8?7 metres, 

 1880 ; Ben Nevis, Scotland, 4,407 feet, 1883. It 

 may be added that Mount Washington was the 

 first, and Pike's Peak is still the highest, mountain 

 meteorological station in the world. 



— The Appalachian mountain club has lately 

 published a copy of the contour-line map of 

 Williamstown and Greylock, as executed by 

 Messrs. Johnson and Natter, topographers of the 

 U. S. geological survey, in the joint topographic 

 undertaking with Massachusetts. The reproduc- 

 tion is on the scale of the original plane-table 

 sheets, 1 : 80,000, and therefore covers an area 

 fourfold that which will be allowed on tlie pub- 

 lication of the map. The district is in the north- 

 western corner of the state, and is well chosen for 

 illustration of the progress and value of the sur- 



vey, as it includes the highest and probably the 

 roughest piece of ground in the commonwealth. 

 The 'hopper' on the western slope of Greylock, 

 and the rugged ridges on the eastern slope, are 

 very well expressed by the contours, although the 

 photolithographic reproduction is not so delicate 

 as could be desired. The cost of the sheet is, 

 how^ever, very moderate, — thnty cents ; for sale 

 by Clarke & Carruth, Boston. 



— The August number of the Alpine journal 

 contains a statement of the results obtained by 

 Dr. Mai'cet from many experiments on breathing 

 while climbing at high altitudes. He first shows 

 by experiments at ordinary altitudes and in a 

 state of rest that some persons make much better 

 use than others of the air they inhale, inasmuch 

 as their exhalation is very rich in carbonic acid : 

 this may be expressed by measuring the volume 

 (at sea-level pressure and freezing temperature) of 

 air inhaled to produce one gram weight of car- 

 bonic acid. Dr. Marcet himself had to breathe 

 15.5 litres of air, while two younger men needed 

 only 13.7 and 10.8 litres respectively : the latter 

 had a i-emarkable power of keeping his bi-eatli 

 under water, and was little troubled in mountain 

 ascents. Further experiments, conducted at 

 various altitudes up to 13,600 feet, show, that, as 

 a person ascends, he breathes fifteen to twenty- 

 five per cent less air (reduced, as above, to stand- 

 ard pressure and temperature) to produce a given 

 weight of carbonic acid : the action of air on the 

 blood in the lungs seems, therefore, to be facili- 

 tated with decreasing density. It is evident that 

 this will materially diminish the quickness of 

 breathing that would otherwise be required in 

 rarefied air. 



— A meeting of the National association for 

 supplying medical aid to the women of India was 

 held at Simla on Sept. 29, Lady Dufferin presid- 

 ing. The reports received from the various 

 provinces were highly satisfactory. The main 

 object now was to establish the association on a 

 permanent footing, for which purpose further 

 funds were required. The estimate for next yeai-'s 

 woi'k showed a surplus ; but, before the financial 

 condition of the undertaking could be called thor- 

 oughly satisfactory, it required a lakh and a 

 quarter more capital. Sir C. Aitchison gave an 

 account of the work done in the Punjab. He said 

 that the province was not rich. The few wealthy 

 men had given what they could, and the move- 

 ment was spreading among other classes. 



— A new laboratory-burner, devised by a Detroit 

 inventor, appears to be both simple and efficient. 

 The base of the burner is provided with a station- 



