282 



SCIENCE. 



[Vol. V., No. 113. 



regularity in observing the stars of the ' Ameri- 

 can ephemeris,' the sun, moon, and planets, 

 and lists of miscellaneous objects chiefly used 

 by exploration parties and expeditions in 

 determining latitudes. In the choice of dates 

 when observations of the bodies of the solar 

 s} r stem, particularly the outer great planets, 

 were made, no systematized plan of opera- 

 tion appears to have been followed. It would 

 be well if the adaptation of the observations to 

 the problems of the future investigator were 

 kept in mind equally prominently with the 

 fact that these bodies, a month or two preced- 

 ing the opposition-time, transit the meridian 

 at inconvenient hours beyond midnight. The 

 da} T s of observation should be so chosen that 

 it will be possible to derive a series of normal 

 places for each planet s} r m metric all}' placed 

 with reference to the epoch of least distance 

 from the earth. 



The great equatorial, with Professors Hall 

 and Holden as observers, was mainly occupied 

 with work upon double stars ; but the satellites 

 of the outer planets were fully observed, as 

 also the great nebula of Orion, the observa- 

 tions on which were published b} T Professor 

 Holden several years ago, in his well-known 

 monograph. 



There is no record of observations with either 

 the prime vertical transit, the mural circle, or 

 the east transit instrument ; and there is very 

 little to show for the lesser equatorial of the 

 observatory. The meteorological observations 

 have been conducted on about the same plan 

 for a long series of years, having been begun 

 long before the Army signal-service was in 

 successful operation as a meteorological bu- 

 reau. If they are continued on the supposition 

 that they form a valuable addition to meteor- 

 ology, this would appear to be an insufficient 

 reason ; while, for an}' known practical bearing 

 on astronomy, they are barely worth the making 

 and printing. 



The volume of observations for the }'ear 

 1879 concludes with two appendixes, the lat- 

 ter of which is a determination of the semi- 

 diameter of the moon from occupations of the 

 Pleiades, b} T Mr. H. M. Paul ; and the former, 

 by Professor Hall, on the parallax of aLyrae 

 and 61 Cygni. In the appendix to the volume 

 for 1880, Mr. Winlock has so collected all the 

 observations and drawings of the ojreat comet 

 of 1882, made at the naval observatory, as to 

 make them available, in considerable part, for 

 definitive discussion of the comet's orbit. 



While, on looking casually through these 

 volumes, one is impressed with the necessity 

 of bestowing greater care on the details of 



proof-reading, it is a pleasure to note the sud- 

 den influx of new types in the printer's fonts 

 from which the latter part of the volume for 

 1880 was set, replacing the old types, which 

 had become so much worn as to make scores 

 of figures on many pages quite indecipherable. 

 With the commencement of the present year, 

 the observatory, under the superintendency of 

 Rear- Admiral Franklin, has begun the execu- 

 tion of a pre-organized plan of astronomical 

 work. This has already been printed and dis- 

 tributed, and the advantages to be expected 

 from this arrangement will be watched for with 

 much interest. 



BRAIN-EXHA USTION. 



This book belongs to a class which finds 

 circulation onl}' in this country, and is not 

 calculated to establish a foreign reputation for 

 the author. If the time spent upon its prep- 

 aration had been given to accurate observation 

 or careful experiment, and the results con- 

 densed into an article of twenty pages, the 

 author might have secured some attention. 

 The work consists of a mass of theoretical 

 statements regarding normal and abnormal 

 brain-action, few of which have any basis in 

 ascertained facts. We know that brain-ex- 

 haustion is possible, and we know under what 

 conditions it occurs. The chapter on causa- 

 tion contains a fair summary of these condi- 

 tions. We do not know the mechanism of its 

 occurrence, and we cannot affirm, in a given 

 case, that a definite line of treatment will 

 succeed. 



The author has a favorite method which it 

 is the object of the book to urge. The 

 method does not commend itself to those who 

 are familiar with recent G-erman investiga- 

 tions by experiment, which, as far as animals 

 go, are directly opposed in their results to the 

 conclusions reached by Dr. Corning. Electri- 

 cal treatment of brain-disease must be con- 

 ducted with caution, and only with the aid of 

 an accurate galvanometer which measures the 

 intensity of the current, and enables the phy- 

 sician to know at any moment what strength he 

 is using. Of this, as well as of other necessary 

 precautions, Dr. Corning seems unaware, for 

 he recommends the use of from ' five to fifteen 

 cells,' a wholly unknown quantity. 



Science demands facts, not theories ; and 

 the sooner this is understood by those who 

 seek a place injts ranks, the better. 



Brain- exhaustion, with some preliminary considerations on 

 cerebral dynamics. By J. L. Corning, M.D. New York, 

 Appleton,\SU. 234 p. 16°. 



