April i8, 1878] 



NATURE 



497 



openings//^ the gas having then a free passage from the pipe 

 a through the two sides of the frame bb, and into and through 

 the phig //. It will be seen on reference to Fig. 6, that a small 

 turn of the plug is sufficient to open or close the cock, k is a 

 pipe screwed into the tube e, and leading to the burner /. m is 

 a projection at the lower end of the plug, and m is a pin passed 

 through the same. The plug is supported on the point of the 

 pivot on which a magnet turn?, so that very little power is 

 required to turn the plug. ^ is a permanent magnet, which may 

 be either cast in steel, with the two projecting pieces p [>, or 

 made out of a steel bar bent into the proper sliape, and in this 

 case the projections// are produced by screwing in two pieces 

 of metal, q is the pivt)t on which this magnet turns ; it is passed 

 through a vertical hole in the magnet, and fixed by a screw r. 

 The lower end of the pivot rests in a steel step j, which is sup- 

 ported by a small wooden beam /, secured to the ends of the 

 wooden bobbin 71. v is the induction-coil ; it is composed of a 

 core of soft iron wire--, two layers of primary wires wound with 

 covered copper wire of about No. 20 BWG, and upon these 

 about ten to fifteen layers of secondary wire of about No. 40 

 BWG. The primary wires zuzu form part of the circuit by 

 which the lamps to be lighted or extinguished simultaneously 

 are connected. One end of the secondary coil is connected to 

 an insulated wire x, leading to the burner /, where it terminates 

 in a platinum point, and the other end is connected to the frame 

 /', or to any other metallic part of the apparatus, so as to be in 

 metallic connection with the burner. The insulated wire x 

 passes through an earthenware support y (seen in plan in Fig. 9), 

 fixed to the pipe /'. The soft iron core projects about three- 

 eighths of an inch from each end of the wooden bobbin «. The 

 bobbin is fastened to wooden supports zz^ which are fixed to the 

 frame b by screws -■:' z^. 



Fig. 10 (for the use of which we are indebted to the Society 

 of Arts) is a view of the complete apparatus as attadud to a 

 gas lamp. 



AMERICAN SCIENCE 



T^IIE March number of the American yournal of Science 

 opens with a valuable paper, in which Prof. Norton 

 collates the various observations made on Coggia's comet. 

 The theory of cometary phenomena he arrives at is (briefly) 

 that the direct action of the sun on the side of the nucleus 

 exposed to the solar rays is to form an envelope of gaseous 

 carbo'nic oxide. This envelope of diamagnetic gas is tra- 

 versed by the ideal lines of magnetic force proceeding from 

 the nucleu', which are also lines of cono notion through the 

 gas. The electricity stt free by the ascending currents of gas, 

 by reason of the diminished gaseous pressure, is propagated 

 along these lines, and the impulsive force of the electric currents 

 detaches streams of the successive molecules of the gas in the 

 direction of the lines of conduction. Both the nucleus and the 

 sun exert repulsive forces on the escaping molecules ; but their 

 effective actions may be either repulsive or attractive, according 

 as their attraction prevails over the attraction of gravitation, or 

 the reverse. The author elucidates this theory at some length. 



In a reply to Mr. Mallet's review (m the /^/lilosophical Maga- 

 zine) of General Abbott's paper on the velocity of transmission 

 of earth-waves, in which the value and accuracy of the Ilallet's 

 Point observations were doubted, the General describes some 

 new observations on the subject, which seem to establish these 

 points : I. A high magnifying power of telescope is essential in 

 seismometric observations. 2. The more violent the initial 

 shock the higher is the velocity of transmission. 3. This velocity 

 diminishes as the general wave advances. 4. The movements of 

 the earth's crust are complex, consisting of many short waves 

 first increasing and then decreasing in amplitude, and, with a 

 detonating explosive, the interval between the first wave and the 

 maximum wave, at any station, is shorter than with a slow- 

 burning explosive. 



A new method for decomposition of chromic iron, proposed 

 by Mr. Smith, consists in exposing it (in an exceedingly fine state) 

 with bromine to a temperature of 180" C. from two to three days. 

 Prof. Marsh furnishes an account of some new Dinosaurian rt p- 

 tiles. — Prof. Kimball describes some experiments on journal 

 friction at low speeds. — There are also notes on some reactions 

 of silver chloride and bromide, brightness of the satellites of 

 Uranus, &c. 



The new number of Appalachia, the journal of the Appala- 

 chian Mountain Club, contains a valuable address by the presi- 



dent, Dr. S. H. Scudder, in which he reviews the principal 

 scientific expeditions in the United States during the past year. 

 Dr. Scudder himself is attached to the Hayden Survey, and 

 made the discovery of the beds of fossil insects at Florissant, 

 near Manitou, Colorado. During the past year 20,cxx) fossil 

 insects have been exhumed from this quarry. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE 



Cambridge.— The fifth and final rejwrt of the Syndicate 

 appointed in May, 1875, to consider the requirements of the 

 University in different departments of study, has been issued. 

 The Syndicate have considered the question of the residence 

 to be required of professors. They are of opinion that it 

 is desirable— (i) that the time for which the University may 

 require the residence of professors shall be left to be determined 

 by the University in the case of each professorship, without any 

 general statutable restriction ; (2) that no professor shall be con- 

 sidered to satisfy the condition of residence who is not for the 

 time required making his home within a mile and a half of Great 

 St. Mary's Church, unless special permission, available for not 

 more than one year at a time, but renewable, be granted by the 

 Vice-Chancellor and Sex Viri, and that such permission shal 

 not lie granted unless the Vice-Chancellor and Sex Viri are 

 satisfied that the professor has made such arrangements as will 

 secure his being reasonably accessible in Cambridge during term 

 time. The Syndicate have also had under their consideration 

 the importance of individual personal intercourse between 

 students and teachers, and it has also been su^ested that the 

 insjiection and revision of students' note -books by the teacher 

 may in many cases be of considerable use. The precise 

 manner in which such jiersonal intercourse may be most 

 effectually secured will probably vary very much in different 

 subjects and for different teachers, but it seems important 

 that the arrangements should be such that the professor 

 himself may in all cases see a portion of the work of his class, 

 so as to make himself accurately acquainted with their wants. 

 The Syndicate have referred to the Board of Medical .Studies 

 the question whether it is desirable to found a complete medical 

 school in Cambridge so as to make it possible for a student to 

 complete his whole medical course here, or whether it is bettor 

 for all concerned, while making the teaching at Cambridge as 

 perfect as possible in the scientific subjects which are the basi^ 

 of medicine, to leave students to carry on elsewhere the greater 

 part of their clinical studies and most of what relates directly to 

 the practice of medicine. The reply of the Board of Medical 

 Studies states that they consider it inexpedient that .students 

 should complete their whole professional education at anj- 

 single medical school, and that it is therefore desirable that 

 students .should pursue their studies away from Cambridge for a 

 year or more before commencing practice, either before or after 

 their final M.B. examination. They believe, however, that it 

 would be in iiiost cases advantageous to students to carry their 

 medical studies in Cambridge further than is usually done at 

 present, and in some cases as far as the final M.B. examination, 

 and they ai-e therefore of opinion that the University should 

 provide systematic instruction in all the subjects necessary for a 

 medical degree, as is done at other Universities. In order that 

 this may be carried out satisfactorily the Board of Metlical 

 Studies think that the University .should provide: — I. A Pro- 

 fessor of Pathology. 2. A Professor of Surgery. 3. Systematic 

 teaching in (i) midwifery and the diseases peculiar to women 

 (2) medical jurisprudence ; (3) sanitary science ; (4) mental 

 diseases. 4. Systematic clinical teaching. 



R.G.S. Public School.s' Prize Medals. — The following 

 is the award of the Public Schools' Prize Medals annually 

 given by the Royal Geographical Society : — Physical Geo- 

 graphy—Gold Medallist, William John Newton, of Liverix)ol 

 College ; Silver Medallist, Christopher Mounsey Wilson, of 

 Clifton College ; Honourably Mentioned — E. G. Ilarmer, Uni- 

 versity College School ; M. II. Clifford and M. A. Soppitt, of 

 Dulwich College ; and J. S. G. Pembcrton, of Eton College. 

 Political Geography — Gold Medallist, William Wallis Ord, of 

 Dulwich College ; Silver Medallist, George Arnold Tomkinson, 

 of Ilaileybury College ; Honourably Mentioned — A, R. Ropes, 

 of the City of London School ; A. Kay, of Rossall School ; 

 and D. Bowie, of Dulwich College. 



