September 30, 1922] 



NA TURE 



465 



accommodation of farm animals under feeding ex- 

 periments. 



The capital outlay, which was estimated in 1920 

 at 40,000/. to 50,000/., will amount to about 46,000/. 

 Of this sum the Treasury, on the recommendation of 

 the Development Commission, provided 20,000/. Mr. 

 John Quiller Rowett, LL.D., generously contributed 

 10,000/., and in addition supplied sufficient funds to 

 purchase the experimental farm. Various smaller 

 sums have been received from other contributors ; 

 but the whole of the necessary funds have not yet 

 been raised. 



The Queen, at the opening ceremony, visited all 

 the departments and talked with the senior workers, 

 asking questions that showed a deep interest in the 

 research work in progress. She was especially 

 interested in the work on indirect calorimetry, and 

 asked to be shown all the apparatus and to have 



the method explained. In the experimental farm 

 she was chiefly attracted by the dairy cows. These 

 are Ayrshires, a breed kept at the Balmoral Estate. 

 She asked questions about the breed and also about 

 milk production in general, which showed an interest 

 in and an appreciation of the importance of the 

 dairy industry. 



After the visit to the different departments the 

 Queen proceeded to the library, where there was 

 a company of about 120, including the Duchess 

 of Atholl, the Duke of Richmond and Gordon, the 

 Marquis and Marchioness of Aberdeen, the Marquis 

 and Marchioness of Huntly, and representatives 

 of public bodies. Here she was presented with a 

 gold key by Dr. Rowett, and formally declared 

 the Institute open. She signed the visitors' book, 

 and before leaving planted a tree in the grounds of 

 the Institute to commemorate the visit. 



The Sun's Activity, 1890-1920. 



SUNSPOTS 

 - „ „ . 2000 



LATITUDES 

 OF 

 SUNSPOTS 



T^HE sun, as is well known, is a variable star having 

 -*- a period of approximately eleven years, but, 

 unlike other stars, its variability can be determined 

 from several different visible phenomena and not 

 solely from the total integrated light emitted. As 

 classed among stars, it is not con- 

 sidered, however, as a regular variable, 

 because the approximate period of eleven 

 years is itself made variable through 

 other minor periods of various lengths. 



Though the sun has a dominating action 

 on many terrestrial phenomena, authorities 

 differ as to the exact relation between the 

 pulsations of the two bodies. It is import- 

 ant, therefore, always to keep in mind, so 

 far as possible, the actual state of solar 

 activity at the moment, i.e. whether the 

 sun is in a quiescent state through lack 

 of spots and prominences, or whether it 

 is in a very turbulent condition caused by 

 their abundance. 



The data for determining the state of 

 the activity of the sun are published 

 separately year by year in various volumes 

 from differentsources, and are only brought 

 together, probably with some difficulty, by 

 research workers who wish to use them 

 for particular inquiries. 



Dr. W. J. S. Lockyer has recently co- 

 ordinated the solar data regarding the 

 sunspotted area, the latitudes of the 

 activity zones of sunspots and promin- 

 ences, together with the variations in the 

 form of the corona for the period 1920 to 

 as near the present as possible. The accom- 

 panying diagram (Fig. 1) illustrates the 

 solar changes in graphic form. The 

 following paragraphs deal briefly with 

 each set of curves individually, including 

 the sources of the data : 



Mi; ax Daily Areas of Sunspots. — 

 Each of the points in the curve repre- 

 sents the mean of the daily areas of 

 sunspots corrected for foreshortening for 

 each year. The values are published by 

 the Astronomer Royal yearly in the 

 Monthly Notices of the Roval Astronomical Society, 

 the last value published being that for 1918 (vol. 82, 

 p. 485). The three later years marked with crosses 

 are only provisional values. 



It will be seen that the maximum spot activity 

 occurred in the years 1893, JQOS. an d 1917, while the 

 years of minimum were 1901 and 191 3. The next 

 minimum will probably fall in 1924 or 1925. 



Latitudes of Sunspots. — Under this heading 

 there are two sets of curves — one for the northern 

 and the other for the southern hemisphere of the sun. 

 Each point represents the mean heliographic latitude 

 of all spots for each hemisphere throughout the whole 



.1890 f 1900 s 1910 



3000- 



LATITUDE OF 

 PROMINENCES' 



S HEMIS 



POLAR 



(■HRESULAI 



INTERMEDIATE 



(SQUARE) 



EQUATORIAL 



year. The data are taken from the same sources as 

 mentioned above. It will be noticed that a new 

 sunspot cycle is always heralded by outbursts of spots 

 in zones of high latitudes (about 22 ), while the zone 

 of spots nearer the equator is dying out. 



Latitudes of Prominences. — Here also there are 

 two sets of curves, one for each hemisphere ; where 

 in the case of the spots there was only one zone for 



NO. 



2761, VOL. I 10] 



