DISCOVERY 



177 



and the creation of a school. In the age of the 

 Antonines, as in our own, the wealthy recognised the 

 responsibility of their riches and were generous 

 givers. The tendency of the time was towards the 

 increasing provision of public institutions for the care 

 and education of children, the encouragement of 

 maternit}', and the maintenance of the aged and infirm. 

 It is interesting to notice, however, a marked difference 

 of opinion between Pliny and a recent benefactor of 

 Scottish universities. The inhabitants of Como had 

 previously been obliged to send their sons to Milan 

 for want of a local school. Pliny determined to remedy 

 this. He initiated the scheme for creating a good local 

 school, and spent some trouble, enlisting the help of 

 Tacitus in the matter, upon securing an adequate staff. 

 But he shrewdly refused to find more than a part of the 

 endowment necessary, not because he grudged the 

 money, but because in his view, as he told his fellow- 

 townsmen, parental responsibility counts for something, 

 and people v'alue more and take a more efficient interest 

 in an institution to the cost of which they contribute 

 themselves. " For though parents may be careless 

 in disposing of another's bounty, they will certainly 

 be cautious how the}' apply their own. and will see that 

 none but those who deserve it shall receive my money, 

 when they must at the same time receive theirs too." 



It will be seen that the general reader who turns to 

 Pliny's Letters for the first time will be likely to modify 

 his conception of the manners and morals of pagan 

 aristocracN' at the turn of the first and second centuries. 

 He ma\' also find plent}' of entertainment and plenty 

 of good things in the book. There are interesting 

 vignettes of social types like the well-read country 

 gentleman (viii. 25), or the eccentric old lady of lurid 

 tastes with her private company of farce-actors and 

 her exemplary grandson (vii. 24). There are charming 

 sketches of Italian country written with a feeling 

 for scenery which is rare in classical authors. There 

 are the two letters to Tacitus describing at first hand 

 the great eruption of Vesuvius. There is a famous 

 ghost story, and finally there is the marvellous relation 

 of the wonderful dolphin of Hippo (ix. 33), a theme 

 which is worthy, though I do not think he has made 

 use of it, of the treatment which Anatole France alone 

 could give it.' 



' Handy and inexpensive pocket editions of Pliny's Letters 

 are the translation by J. B. Firth, published by the Walter 

 Scott Publishing Co., and the text and translation edited by 

 W. M. L. Hutchinson for the Ix)eb Library. Though I have 

 made use of both above, the second is perhaps preferable, 

 for not only does it give the Latin text opposite the translation, 

 but the latter is a revision of an English classic, the translation 

 of William Jlclmoth first published in 1746. 



For the social conditions of the period Dill, Roman Society 

 from Xero to Marcus Atireliiis. and Friedlaender (translated by 

 Magnus), Roman Life and Manners under the Early Empire, 

 may be consulted. 



Recent Advances in our 

 Knowledge of the Sun 



By the Rev. Hector Macpherson, M.A., 

 F.R.A.S., F.R.S.E. 



SoL.A.R astronomy, as a distinct branch of the science, 

 dates from the closing years of the eighteenth century. 

 The elder Herschel, amid his multifarious investigations, 

 found time for the systematic study of the solar disc ; 

 and to him is due the credit of enunciating, as the 

 outcome of his scrutiny of the spots and faculae, the 

 first " solar theory "worthy of the name, a theory which, 

 although fallacious, actedas a stimulus to further investi- 

 gation. In the historj' of solar research since Herschel's 

 time, three well-defined periods may be traced. The 

 first, which may be designated the telescopic period, 

 opened in 1826, when Heinrich Schwabe, the amateur 

 astronomer of Dessau, began to count the number of 

 spots visible daily on the solar disc, an investigation 

 which ultimately resulted in the discovery of the solar 

 cycle — the increase and decrease of the number of sun- 

 spots in a period of about eleven years — which was 

 shown to be synchronous with the period of terrestrial 

 magnetic variation. In this period, too, Carrington, in 

 England, and Sporer, in Germany, independently 

 discovered the remarkable equatorial acceleration of the 

 sun. They showed that the sun's rotation period 

 increased from about 25 days at the solar equator to 

 about 27 i days midway between the equator and the 

 poles. 



The second, which may be called the spectroscopic 

 period, opened in 1859, when the newly-invented spec- 

 troscope was applied by Kirchhoff to the study of the 

 sun, and the sub-science of solar physics was born. By 

 means of the spectroscope many of the familiar ter- 

 restrial elements were identified in the solar atmosphere. 

 The spectroscope was also applied by Janssen and 

 Lockyer to the daj-light study of the solar promi- 

 nences, those red flames which were formerly revealed 

 only on the rare occasions of total eclipses. The 

 systematic work of the Italian school of spectroscopists — 

 Secchi, Respighi, Tacchini, and Ricco — brought out the 

 significant fact that the number and distribution of the 

 prominences were governed by the same law as the 

 spots ; in other words, obeyed the solar cycle. Perhaps, 

 however, the application of the spectroscope to the 

 measurement of motion was the most important 

 development during this period. In 1842 Christian 

 Doppler, of Prague, pointed out that, theoretically, 

 the colour of a luminous body should be changed by 

 motion of approach or recession, just as the sound of a 

 sonorous body is altered ; the change in colour, how- 



