September 9, 1887.] 



SCIENCE. 



129 



a series ; and doubtless the book, which is a novel one, will prove 

 useful alike to professors, assistants, and students. Its primary 

 purpose is that of a laboratory guide. 



Four Figure Maiheniatical Tables. By J. T. Bottomley. Lon- 

 don, Macmillan. 12°. 

 This is a series of mathematical tables comprising logarithmic and 

 trigonometrical tables, and tables of squares, square roots, and re- 

 ciprocals. In an appendix are contained a number of useful formulas 

 and numbers, especially for those engaged in work in physical la- 

 boratories. The book is compiled by a lecturer in natural philoso- 

 phy in the University of Glasgow. 



NOTES AND NEWS. 



In order to expedite the publication of short articles upon astro- 

 nomical and meteorological subjects which may be prepared at 

 Han'ard College Observatory, it has been decided to print them as 

 successive numbers of a series, which will constitute the eighteenth 

 volume of the ' Annals of the Observatory ' when a sufficient 

 amount of material has thus been collected. Each number will be 

 pubHshed and distributed soon after it has been prepared. 



— During this month will appear, under the editorship of Dr. G. H. 

 Rohe, a quarterly journal, The Climatologist , devoted to the con- 

 sideration of questions in the domain of medical and sanitary cli- 

 matology. As there is at present no other journal in the world 

 exclusively occupying this special field, the editor and publishers 

 believe that there is room for such a publication. Each number 

 will contain forty-eight quarto pages of reading-matter, the sub- 

 scription price will be fifty cents per year, and the place of publica- 

 tion, S. E. Cor. Baltimore and South Streets, Baltimore, Md. 



— Dr. John Vansant of the United States Marme Hospital at St. 

 Louis claims to be the first to have taken photographs by the light 

 of fireflies. He placed twelve fireflies in a three-ounce bottle, 

 covering its mouth with fine white bobinet. The average duration 

 of the flash of each insect was half a second, and the luminous area 

 on the abdomen was about one-eighth of an inch square. The 

 time of exposure was fifty flashes. 



— Lieut. J. F. Moser, U.S.N., commanding the Coast Survey 

 steamer ' Bache,' has just submitted a report of the hydrographic 

 work executed by that steamer from Cedar Keys southward to a 

 point off Chasahowitzka River, and the finishing of the hydrog- 

 raphy from Cape Romano to the delta of the Mississippi. He 

 refers to the great difficulty of running triangulations, owing 

 mainly to the obscurity or entire absence of former triangulations, 

 or other ear-marks of the locality to be surveyed. St. Martin's 

 Reef was found to continue as far north as Homosassa, thence 

 trending eastward to join the shallow waters of Crystal River. 

 It is on the Florida banks, of which St. Martin's Reef forms 

 an inshore part, that many of the commercial sponges are taken, 

 and a large number of vessels are yearly engaged on the work. 

 The tides in this locality were found to be easily affected by winds, 

 causing great irregularity in their range, stand, and times of move- 

 ment. The coast was found to be low and rocky, and the entire bot- 

 tom covered with porous rock. The anchorage off St. Martin's Reef 

 is good and safe in any weather except a hurricane. Lieutenant 

 Moser says the country is dreary, desolate, and uninhabited, and 

 the coast-line consists of fringing islands, thickly covered with 

 mangrove. On these islands oysters are found growing in trees, 

 the spawn having attached themselves to the branches at high 

 water and developed into oysters. Bird-life was not abundant, 

 even sea-gulls being conspicuous by their absence. Rail and blue 

 and white herons were found, but even these birds have been 

 driven away by the plume-hunters. 



— A. Auwers has thoroughly discussed the alleged periodical 

 changes of the diameter of the sun, and finds that in fact they do not 

 exist. His researches, which are founded on 19 series of observa- 

 tions, — 12 of which refer to the horizontal diameter, and comprise 

 21,000 obser\'ations, while 7 refer to the vertical diameter, — show 

 that the periodical changes are due to the influence of the tempera- 

 ture upon the instruments with which the observations were made, 

 and that for this reason the period corresponds to that of the annual 

 period of temperature. 



LETTERS TO THE EDITOR. 

 Experimental Physics for Schools. 



For years one of the requirements for admission to Harvard 

 College has been such knowledge of physics as may be obtained 

 from the study of any one of certain well-known elementary text- 

 books. To this requirement is now added the study of a certain 

 astronomical text-book, but as an alternative to both the text-book 

 physics and the astronomy there is recommended a course of study 

 in physics involving considerable laboratory work on the part of the 

 pupil, supplemented by instructions from a text-book or a course of 

 lectures. 



Two questions suggest themselves to the teacher of physics when 

 he finds himself met by the proposition to give laboratory practice 

 to a whole class: ist. Is this desirable if practicable.' 2d. Is it 

 practicable ? 



Without undertaking to discuss at large the theory of a liberal 

 education, we can note a few considerations which will enable us to 

 answer the first of these questions with some confidence : ist. 

 Physics is studied partly for training and partly for information. 

 2d. Text-book physics alone gives but little training that cannot be 

 given by arithmetic, algebra, and geometry, all of which studies are 

 pursued by the pupil before he enters college. 3d. Physics as 

 taught by the laboratory experience of the pupil gives a kind of 

 training that is not given by any course of study required for ad- 

 mission to Harvard College or, perhaps, any other college in the 

 country. This training is partly of the senses and partly mental. 

 It is true that many book-studies educate the senses to a certain ex- 

 tent, and the logical faculties, but unfortunately it is possible for a 

 person who is observing and logical in things which he is in the 

 habit of studying to be quite the opposite in dealing with things 

 which do not habitually occupy his mind. Now, laboratory physics 

 is the only elementary study for admission to Harvard College that 

 requires the student to look beyond the pages of a book, and al- 

 though most students do look at other tjiings than books, they are 

 not in the habit of studying things outside of books. 4th. The in- 

 formation given by the text-book alone is wide but superficial and 

 vague. It is like that knowledge of a country which one may get 

 by travelling rapidly over it on a railroad train. 5th. The informa- 

 tion given by laboratory practice alone is definite but narrow. It is 

 like that knowledge of a country which one would get if he tried to 

 go over the whoie of it on foot. 6th. Most students show far more 

 interest in laboratory work than in the study of a text-book, even 

 when the same subjects are dealt with in both cases. Much of the 

 repugnance which many students feel for physics as they study it 

 comes from the almost painful effort of the imagination to body 

 forth the things described in the text-books, and which might be 

 seen directly and handled in the laboratory. 



From these considerations vi'e reach the conclusion that the 

 course which Harvard recommends to preparatory schools is desir- 

 able, if practicable, viz., to have the pupil study intimately certain 

 topics by the laboratory method, and to enlarge upon, apply, and 

 connect the knowledge so gained, by means of a text-book or a 

 course of lectures. In the opinion of the writer, a course of 

 lectures sufficiently extensive and systematic to take the place of a 

 text-book for this purpose is beyond the present powers of most 

 preparatory schools. 



It may be hoped that by following such a course in physics the 

 student will escape, on the one hand, a condition of blind and 

 helpless dependence upon text-books, and, upon the other hand, the 

 scarcely less unfortunate state of self-sufficiency which cannot or 

 will not profit by the literature of the science. 



Harvard University has issued for the use of teachers engaged in 

 preparing students for its college classes a pamphlet giving a list of 

 forty laboratory exercises, with specifications of the apparatus and 

 materials to be used in these exercises, and with directions for their 

 performance, or references to manuals giving such directions. These 

 exercises are to be performed by the pupil. To speak cursorily, they 

 deal' with certain distinctive characteristics of the solid, liquid, and 

 gaseous states of matter, the determination of specific gravities, the 

 first principles of statics and dynamics, evaporation and boiling, the 

 determination of the fixed points of a thermometer, expansion of solids 

 and gases, specific heat, latent heat, velocity of sound, interference of 



