H 



NATURE 



[Nov. 5, 1874 



EARLY OPENING OF KEW GARDENS 



OUR readers are no doubt aware that a movement has 

 been set on foot for the earlier opening of Kew 

 Gardens, a step which, If taken, would, we believe, wholly 

 alter the character of that institution. It would, we feel 

 assured, seriously interfere with all scientific work, and 

 with the uses which we hope will one day be made of 

 the gardens in the mornings by science schools. More- 

 over, we doubt if there exists any general desire for 

 their early opening,^ and are inclined ^to believe that 

 the movement is quite local in its origin and extent. On 

 this subject we are glad to quote the remarks in a recent 

 number of the Ecoiuvuisi, both on account of their per- 

 tinency and force, and because we rejoice to see the true 

 interests of science advocated by papers not professedly 

 scientific : — 



" The question has been mooted of late whether the 

 Royal Botanic Gardens at Kew could not be opened to 

 the public at an earlier hour than the present time of 

 I p.m. A little reflection will enable those who ask this 

 question to perceive that it can scarcely be answered in 

 the affirmative without inflicting a serious injury on the 

 real utility of the gardens and on the public service. In 

 the first place, all the real work of the gardens has to be 

 done during the hours when they are closed to the public. 

 As it is, this time is barely long enough for the duties 

 which have to be performed in it. To open the gardens 

 in the morning would require a second staff of gardeners 

 and workmen, as strong, or nearly so, as the existing one. 

 Even with this extra assistance and this greatly increased 

 cost, the work could not be as well executed as it is at 

 present. In the next place, as the name of the gardens 

 implies, they are botanic gardens. Besides those who 

 ordinarily frequent the gardens for pleasure, there are 

 many artists and scientific men who visit them for 

 purposes of study ; the only time when they can do 

 this with advantage is before the general public are 

 admitted. 



" Of late the public has come in rushes of 12,000 to 

 60,000 in a day. If only 10,000 persons were in the 

 gardens in the forenoon, all work would necessarily be at 

 an end, and it would be impossible to maintain the exist- 

 ing character of the place. As it is, the Botanic Gardens 

 at Kew are more accessible to visitors than any other 

 public institution. Week days and Sundays alike the 

 gates stand open. At the British Museum and the 

 National Gallery— between the hours of opening which 

 and the gardens at Kew comparisons have been drawn — 

 there are many hours and even days when those institu- 

 tions are necessarily closed to the public for purposes of 

 cleaning, putting in order, and making good the results 

 of the wear and tear of the enormous traffic. But if the 

 heads of those institutions had, like the Director of the 

 Royal Gardens at Kew, to grow what they exhibit, they 

 would doubtless require many more close days than they 

 do at present. 



" Nor is it merely the work of maintaining the gardens 

 and grounds in their present efficiency which has to be 

 carried on in those hours during which the gates are 

 closed to the public. It should not be forgotten that the 

 Royal Gardens at Kew have performed services to the 

 British Empire which no other public institution could 

 undertake. The successful introduction of the Cinchona 

 tree into India (a resource to that country the importance 

 of which cannot be over-estimated), the efforts being 

 made at the present time to procure fresh and improved 

 coffee for Ceylon— to single out only two from a host of 

 similar instances in which the Director of Kew Gardens 

 has freely placed his botanical science and invaluable 

 practical knowledge at the service of the public — will 

 show how diversified and extensive the operations of the 

 gardens are. To prevent these being carried out as they 

 are at present, would be a serious injury to the public 



service. The present Director, Dr. Hooker, and his 

 father, Sir W. T. Hooker, who held the same office before 

 him, have done everything in their power, consistently 

 with the proper maintenance of the gardens in due 

 working order, to facilitate the use of them by the public 

 generally ; and in the interest of science as well as for the 

 prosperity of the gardens, it is to be hoped that the 

 public will see the desirableness of being satisfied with the 

 present very ample allowance of opportunity for visiting 

 the Botanic Gardens at Kew, and that they will not 

 insist on acting over agam the fable of the goose and the 

 golden eggs for the sake of a little present pleasure." 



THE GEOGRAPHICAL DISTRIBUTION OF 

 A URORyE 



J N an interesting paper in Petermann's Mittheilimgen 

 ■'• for October, Prof. Fritz gives the results of his 

 extensive researches on this subject. The investigation 

 is beset widi difficulties, not only from the deficiency of 

 observations, but from their irregularity. While some 

 observers content themselves with noting only the more 

 remarkable displays, others register the faintest light to 

 the north as an aurora. One observer continues his 

 observations for tens of years, while another, whose zeal 

 has been roused during a period of maximum frequency, 

 allows it to cool when a minimum, with its i-are and 

 feeble displays, again returns. The research is further 

 complicated by the fact that the appearance is not only 

 dependent on latitude, but undergoes a periodic change, 

 which in the region of most frequent display manifests 

 itself less in diminished number than in diminished 

 intensity of aurora ; and because in some places the 

 phenomenon is far more frequently concealed by a cloudy 

 sky than in others. 



As far as possible to eliminate these sources of error, 

 Prof Fritz compares the mean number of observations 

 for any given place with the mean for mid-Europe be- 

 tween 46° and 55" lat. (or between the English and 

 Scotch boundary and the Alps) for the same period, by 

 the following formula : — 



M = _C . ?=,8B 

 172 E E 



where M is the mean calculated frequency for the given 

 place, C the total number of aurora in the author's cata- 

 logue for mid-Europe from 1700 to 1871=4830, B the 

 number of aurora: for the period of observation for the 

 given place, and E the number from the author's cata- 

 logue for mid-Europe for the same period. Thus, for 

 example, he calculates for Christiania : — 



1837-1854 B = 529 E = 581 M = 25'S 

 1855-1870 B = 436 E = 568 M = 21-9 

 1837-1870 B = 965 E = 1,149 M = 23-3 



As we have already remarked, a complete agreement 

 of the different mean values is not to be expected, both 

 on account of errors of observation, and from the various 

 local influences of climate and situation. Professor 

 Fritz gives tables of the numbers of observed aurora;, and 

 calculated values of M for upwards of 200 places in 

 Europe, Asia, and America ; and from these, proceeds to 

 lay down on a chart of the northern hemisphere a series 

 of curves of equal frequency of auroral display, which 

 he calls isochasinen. He discusses with great care the 

 probable value of the observations, and lays down the 

 curves so as to include on either side of them as many 

 observations above as below the required value. But a 

 few instances ^willniake .his method clearer than any 

 description. 



The zone M = o-j passes through the southermost part 

 of Spain, through Calabria, and just north of the south 

 coast of the Black Sea, through the Sea of Aral and 

 Lake Balkchash, south of Saghalien and the Kurile 



