May 2, 1872] 



NATURE 



everywhere like rain. The plantations were covered with 

 tlicm, and people were walking with umbrellas to protect 

 themselves from the downpour. The rain of burning 

 scoriiE has reached as far as Scafati and Palermo. 

 Readers of Prof. Phillips's work on Vesuvius will recollect 

 that he throws considerable doubt on the correctness of 

 the popular idea that Vesuvius emits _flainc during an 

 crruption, though he thinks there are one or two authentic 

 instances of this rare phenomenon. The accounts at 

 present received do not throw much light on this point. 

 One narrator stales " Mount Vesuvius is displaying terrible 

 electric phenomena, marked by flashes of lightning and 

 vibrations of the earth ;" and another, that "flames are 

 bursting through several craters." Other accounts speak 

 merely of the eruption of glowing lava and smoke brightly 

 iUuminated by it, and this may readily have been mis- 

 taken for flame. 



Great credit is due to Prof. Palmieri, who has remained 

 at his post at the Observatory to watch the emption, and 

 from whose observations a great advance of science may 

 be anticipated. On Monday at noon he telegraphed as 

 follows : — " Scorire in great abundance have fallen in the 

 direction of the Observatory. The instruments at the 

 Observatory are very much disturbed. The projectiles 

 from the volcano rise to a height of more than a kilo- 

 metre. The lava has ceased to flow." 



It is satisfactory to know that recent letters speak of 

 the first reports of the loss of life as having been some- 

 what exaggerated. Eighty persons are now stated to be 

 missing ; all Italians. Thirteen wounded were taken to 

 the hospital ; of these six are dead. No English or 

 Americ ans are reported dead or wounded. 



The latest telegrams received at the moment of going 

 to press speak of an enormous column of "fire" being 

 visible from Naples. Explosions, accompanied by shocks 

 like those of an earthquake, were constantly occurring. 

 Prof. Palmieri telegraphed from the Observatory on 

 Tuesday that the roar of the volcano had ceased. 

 Numerous flaming projectiles continued to be launched 

 into the air, but with less force than previously. The 

 smoke had decreased, and the shocks, though frequent, 

 were not of a dangerous character. 



SCIENCE PRIMERS 

 Science Primers : " Chemistry," by Prof. Roscoe ; 



" Physics," by Prof. Balfour Stewart. (London : Mac- 



millan, 1872.) 

 ' I 'HESE little books illustrate an imperfectly accepted 

 i~ truth, that systematic elementary teaching is a late 

 and not an early product of educational energy. The 

 best headmasters of our schools have discovered the fallacy 

 latent in our ancient belief that the ablest men are re- 

 quired to teach the oldest boys, and have in one or two 

 famous cases acted on their discovery. It is easy for a 

 young man fresh from University honours to pour his 

 knowledge into minds which have been well prepared, 

 and which approach more or less to the level of his own ; 

 but to teach a class of little boys, to realise their difficulties 

 and to appreciate their ignorance, to understand the per- 

 plexity which oppresses them in the presence of state- 

 ments long since axiomatic to ourselves, requires a 

 mature and versatile intelligence, a mind which can com- 



municate childish knowledge as readily and as joyously 

 as it solves recondite problems ; a combination of rare 

 gifts with long and conscientious training. 



And thus it is that the zeal for scientific teaching and 

 the gathered scientific experience of the last fifteen years 

 have only issued now in the books which form the sub- 

 ject of our notice. Scientific class-books hitherto have 

 been either too diflScult or too easy. They have been 

 unavailable for beginners without the intervention of a 

 practical teacher ; or in their effort to be popular and 

 simple they have abdicated half their value as instruments 

 of educational discipline. In these books both extremes 

 are avoided. Every stage of their teaching is based upon 

 experiment ; no law is enunciated till it has been proved. 

 From first to last the student finds himself in immediate 

 contact with Nature. His empirical knowledge of ex- 

 ternal things is systematised ; simple every-day phenomena 

 reveal to him their principles and rationale ; he walks 

 forth with a new eye to discern the meaning and the 

 beauty of familiar sights and sounds, and with a mind 

 upon the stretch for fresh discoveries. And, on the other 

 hand, no previous training is essential to the teacher who 

 adopts them as his guide. Any man, ignorant even of the 

 first principles of chemistry and physics, yet fairly dex- 

 terous and intelligent, who will patiently master the books, 

 and try each experiment for himself, is in a position to 

 transmit their contents successfully and clearly. The 

 officer may lecture to the soldiers of his regiment, the 

 clergyman to the artisans of his parish, the national 

 schoolmaster to the children of his school. Managers of 

 middle schools, deterred as yet from including science in 

 their course through lack of teachers and of text-books, 

 will find their difficulty removed. The higher schools 

 need no longer confine their scientific teaching to the 

 senior forms, but may place the " Science Primer " along 

 with the Latin grammar, in thehands of their youngest boys. 



The expense of apparatus need not be considered for- 

 midable. A complete set for the course of Chemistry is 

 set down at 5/. iojt., for Physics at 19/. 3^'. Zd. This last, 

 however, includes such costly implements as the air- 

 pump, balance. Grove's battery, and electrical machine. 

 Leaving these to be obtained by special donation or 

 borrowed for the occasions of their use, and deducting 

 such further instruments and utensils as a handy man can 

 make or convert at trifling cost, the outlay for the two 

 courses may be bought considerably under 10/. And 

 since the apparatus once established will require rare and 

 slight renewal, one may hope that a moderate number of 

 pupils with a moderate scale of fees would always pro- 

 vide this sum, more especially if the South Kensington 

 authorities, in the presence of these manuals and of the 

 revolution they may be expected to work, can be induced 

 to extend the limits under which they furnish educational 

 materials at half-price. 



The names appended to the books guarantee their 

 scientific accuracy, and their embodiment of the latest 

 knowledge ; but from the teacher's point of view they ex- 

 hibit some few statements which are not quite clear, and 

 which may deserve reconsideration. In the Chemistry 

 Primer (Experiment 3, p. 7) the caustic soda is left unsup- 

 ported in the tube. The description is probably com- 

 pelled to follow the engraving ; but most lecturers would, 

 as is suggested in the appendix, use the U tube in such a 



