Maech 12, 1915] 



SCIENCE 



396 



Spencer, director of the mineralogical depart- 

 ment of the Britisii Museum, in 1904. 



George F. Kunz 



Optic Projection. Principles, Installation and 

 Use of the Magic Lantern, Projection Micro- 

 scope, Eeflecting Lantern and Moving Pic- 

 ture Machine. By Simon Henry Gage and 

 Henry Phelps Gage. The Comstock Press, 

 Ithaca. 1914. Pp. Y31. $3.00. 

 Professor Gage and his son. Dr. Gage, have 

 written a timely and compendious treatment 

 of optical projection that will be heartily wel- 

 comed by all who are interested in the subject. 

 Such recent developments of the art of pro- 

 jection as cinematography and opaque projec- 

 tion are discussed at length, while the older 

 ordinary forms of projection are not neglected. 

 The titles of the fifteen chapters are, in order : 

 Magic Lantern with Direct Circuit; Magic 

 Lantern with Alternating Current; Magic 

 Lantern for Use on the House Electric Light- 

 ing System; Magic Lantern with the Lime 

 Light; Magic Lantern with Petroleum Lamp, 

 with Gas, Acetylene and Alcohol Lamps; 

 Magic Lantern with Sunlight, Heliostats ; Pro- 

 jection of Images of Opaque Objects ; Prepara- 

 tion of Lantern Slides ; The Projection Micro- 

 scope; Drawing and Photography with Projec- 

 tion Apparatus; Moving Pictures; Projection 

 Rooms and Screens; Electric Currents and 

 their Measurement, Arc Lamps, Wiring and 

 Control, Candle Power of Arc Lamps for Pro- 

 jection; Optics of Projection; Uses of Projec- 

 tion in Physics, Normal and Defective Vision. 

 In addition there is given a historical outline 

 of the origin and development of projection 

 apparatus, a list of manufacturers of and 

 dealers in projection apparatus, a bibliography 

 and an index of both names and subjects. 

 There are 413 cuts and diagrams. 



The authors state that their aim has been to 

 explain the underlying principles upon which 

 the art of projection depends and to give such 

 simple and explicit directions that any intelli- 

 gent person can succeed in all the fields of 

 projection. The point of view throughout is 

 that of the skilled amateur. To the profes- 

 sional operator the treatment will appear aca- 

 demic, to the theorist it will appear very prac- 



tical, but all will agree that it covers the 

 middle ground clearly and exhaustively. 



P. G. Nutting 



TEE METEBOLOGY OF ADELIE LAND, 

 ANTASCTICA 



The climatic facts set forth by Sir Douglas 

 Mawson in his interesting volumes, " The 

 Home of the Blizzard," reviewed last week in 

 Science, justify his claim that it is the 

 stormiest spot on the face of the earth. Al- 

 though the data as to the weather are desultory 

 and incomplete, except as to the winds, yet a 

 brief survey of this newly discovered lancT is 

 of scientific interest. Fortunately the expedi- 

 tion was equipped with recording instruments 

 for barometer, sunshine, temperature, wind, 

 etc., so that data exist for full and satis- 

 factory discussion of local meteorology in the 

 promised scientific volumes. Observations 

 were made at the main base. Commonwealth 

 Bay, 6Y° S., 133° E., and by the sledging 

 parties through King George Land. 



No table of monthly means of any kind are 

 given, but it is stated that the mean tempera- 

 ture for the first year was slightly above zero. 

 This is an exceedingly low temperature for 

 the latitude, 67° S. It is, however, not a local 

 cold of radiation, but a cold of translation 

 through the continuous and violent downflow 

 of air from the elevated plateaus of Antarctica, 

 11,000 feet or more above sea level. The sharp 

 pitch of the land is shown by the rise of 1,900 

 feet in fourteen and a half miles from the sea. 

 The temperatures were never exceeding low, 

 but were steadily maintained. The minimum 

 temperature at the seacoast was only — 28°, 

 and the lowest observed on the ice-cap of the 

 hinterland during the spring sledging was 

 — 35°; on September 18, 1912. 



From a shaft excavated in the neve of the 

 hinterland, at an elevation of 2,900 feet, Bage 

 calculated that the mean temperature of the 

 snow, which would be higher than the air, for 

 the year was approximately — 16°. It would 

 not be unreasonable from these data to place 

 the mean annual temperature of the south- 

 polar plateau at —40°. The contrast between 

 temperatures during high winds and in pe- 



