NATURE 



[June 19, 1890 



.4- inch object-glass referred to in the last Report was mounted on 

 the Sheepshanks equatorial, and i8 photographs were taken 

 with it last summer, the lenses being separated for photographic 

 achromatism, and the crown lens reversed to correct for the 

 spherical aberration introduced by the separation. The best 

 distance of separation was determined, and the photographs 

 obtained were found to be quite satisfactory. The completion 

 of the 28-inch object-glass has been delayed presumably by the 

 pressure of work on the 13-inch photographic telescopes, which 

 have engaged so much of Sir H. Grubb's attention, but it is 

 hoped that the new refractor will be ready for mounting very 

 shortly. 



The 13-inch photographic refractor, with lo-inch guiding 

 telescope, by Sir H. Grubb, has been lately mounted in the 

 new 18-foot dome, and one or two trial photographs have been 

 taken with it. 



Since the date of the last Report, 14 occultations of stars by 

 the moon (9 disappearances and 5 reappearances) and 13 

 phenomena of Jupiter's satellites have been observed with the 

 equatorials, or with the altazimuth. These observations are 

 completely reduced to the end of 1889. The occultation of 

 Jupiter by the moon on August 7 was observed with 5 instru- 

 ments. 



Comets have been observed with the Sheepshanks equatorial 

 on II nights as follows: Comet a 1889 on 6 nights, Comet d 

 1889 on I night, Comet a 1890 on 4 nights. 



The conjunction of Mars and Saturn on September 19 was 

 observed with the south-east equatorial under favourable atmo- 

 spheric conditions, and nineteen differential observations made of 

 right ascension and north polar distance. 



As regards spectroscopic and photographic observations, 457 

 measures have been made of the displacement of the F line in 

 the spectra of 36 stars, and 20 of the b line in the spectra of 5 

 stars for determinations of motions of approach or recession. 

 Observations of Algol on 7 nights confirm, as far as they go, 

 the previous results indicating orbital motion. The observa- 

 tions of Spica made in past years are found by Prof. Bak- 

 huyzen to be tolerably well represented on the hypothesis of 

 orbital motion with a period of 4 days o'386 hours, which 

 agrees well with that recently discovered by Dr. Vogel with his 

 photographic method. As the series of observations with the 

 I2|-inch refractor (extending over 15 years) will be shortly 

 brought to a conclusion, it is proposed to discuss them with a 

 view to the detection of orbital motion. The spectra of R An- 

 dromeda, X Cygni, and Uranus, have been examined on several 

 occasions, and Comet e 1889 on i night. 



The sun has been free from spots on 211 days in the year 

 1889, the longest spotless period being October 23 to December 

 .11. There were also eight other spotless periods of more than 

 a fortnight. The mean daily spotted area in 1889 was 78, as 

 compared with 89 for 1888 : but the mean daily area for the 

 latter half of the year was nearly twice as great as for the earlier 

 half, being 103 as compared with 53. Again, the mean dis- 

 tance of spots from the equator was 5°'46 in the first six months, 

 and 14° 72 for the last six ; and both these facts thus point to 

 the middle of the year 1889 as a well-defined date for the sun- 

 spot minimum. 



The following are the principal results for the magnetic 

 elements for 1889: — 



Mean declination I7 34'9 



Mean horizontal force / 3-9494 (in British units). 



Mean dip 



1*82x0 (in metric units). 



( 67 22 52 (by 9-inch needles). 

 I 67 23 58 (by 6-inch needles). 

 ( 67 25 36 (by 3-inch needles). 



In the year 1889 there were only two days of great magnetic 

 •disturbance, but there were also about twenty other days of 

 lesser disturbance, for which tracings of the photographic curves 

 will be published, as well as tracings of the registers on four 

 typical quiet days. 



The mean temperature of the year 1889 was 48° '8, being o°'4 

 below the average of the preceding 48 years. The highest air 

 temperature in the shade was 86°'6 on August i, and the lowest 

 j8°7 on March 4. The mean monthly temperature in 1889 was 

 below the average in all months excepting May, June, and 

 November. In February and December it was below the 

 average by 2° -4 and 2° '2 respectively, and in May above by 

 3"'9. 



NO. 1077, VOL. 42] 



The mean daily motion of the air in 1889 was 245 miles, 

 being 39 miles below the average of the preceding 22 years. 

 The greatest daily motion was 736 miles on October 7, and the 

 least 25 miles on September 3. The greatest pressure registered 

 was 15 lbs. on the square foot on October 7. 



The number of hours of bright sunshine recorded during 1889 

 by the Campbell-Stokes sunshine instrument was 1156, which is 

 about 146 hours below the average of the preceding 12 years, 

 after making allowance for difference of the indications with 

 the Campbell and Campbell-Stokes instruments respectively. 

 The aggregate number of hours during which the sun was above 

 the horizon was 4454, so that the mean proportion of sunshine 

 for the year was 0-260, constant sunshine being represented by i. 



The rainfall in 1889 was 23-3 inches, being 1-3 inches below 

 the average of the preceding 48 years. 



It was mentioned in the last Report that the Indian invariable 

 pendulums had been mounted in the Record Room under General 

 Walker's supervision. The three pendulums have each been 

 swung 8 times, at pressures of both 2 inches and 27 inches, and 

 the observations completely reduced, giving the following results 

 for number of vibrations in a mean solar day, reduced to vacuum, 

 a temperature of 62°, an infinitely small arc, and sea-level ; 

 the corresponding values obtained at Kew being appended for 

 comparison : — 



Kew. 

 86,166-50 

 86,06661 

 86,117-03 



The tabulation of results for the period of the fifty years of 

 observations will be completed at the end of this year, and will 

 be useful for many purposes. In the twenty years' meteorologi- 

 cal reductions, the values were grouped generally in month?, 

 mainly for the determination of diurnal inequalities of the ther- 

 mometer and barometer. In the tables of meteorological aver- 

 ages now proposed, however, the values will be grouped by days, 

 so as to exhibit mean values for each day of mean daily tem- 

 perature, maximum, minimum, barometer, velocity of wind, 

 frequency of gales, rainfall, and cloud, obtained from the 

 Greenwich observations of fifty years, 1841-90. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Cambridge. — The following are the speeches delivered by 

 the Public Orator (Dr. Sandys, tutor of St. John's College) in 

 presenting Sir Andrew Clark, Mr. Jonathan Hutchinson, Dr. 

 John Evans, Prof. Sylvester, and Mr. A. J. Ellis for honorary 

 degrees on June 10 : — 



Salutamusdeinceps salutis ministrum, Aesculapii e filiis unum, 

 quem idcirco praesertim Machaona nominaverim quod saeculi 

 nostri oratorum cum Nestore ipso totiens consociatus est ; — nisi 

 forte, Romano potius exemplo delectatus, mavult Asclepiadis 

 illius disertissimi nomen mutuari, quo medico et amico utebatur 

 Lucius Licinius Crassus, saeculi sui oratorum eloquentissimus. 

 In re publica partium liberalium studiosus, in re privata liberali- 

 tate singulari insignis, non modo medicinae sed etiam philo- 

 sophiae et religionis penetralia ingressus est. Etiam antiques 

 meministis quondam non de corporis tantum salute sed etiam de 

 rebus fere omnibus quae vitam anxiam et sollicitam reddant, ab 

 ipso Aesculapio solitos esse oracula exposcere. Viri talis igitur, 

 velut iurisconsulti Romani, domus, est velut civitatis oraculum, 

 unde cives eius, ut Apollo Pythius apud Ennium dicit, consilium 

 expetunt, non salutis tantum sed etiam " summarum rerum 

 incerti," quos incepti certos "compotesque consili dimittit." 

 Ergo virum, quem aut litterarum aut scientiae aut medicinae 

 doctorem nominare potuissemus, iuris doctorem non immerito 

 creamus. 



Duco ad vos medicinae professorem emeritum, Regii Medi- 

 corum Collegii Londinensis praesidem, baronettum insignem, 

 suavem, eruditum, eloquentem. An dream Clark. 



Etiam alter Aesculapii filiorum, Podalirius (nisi fallor), hodie 

 nobis sese praesentem obtulit, quem a fratre suo idcirco disiungere 

 neque possumus neque volumus, primum quod professoris in 

 munere quondam erat coUega eius coniunctissimus, deinde quod 

 forte quadam domum vicinam atque adeo proximam incolit, 

 denique quod dignitate non minore Collegio alteri praesidet, ubi 



