November io, 1910] 



NATURE 



45 



Roman roads, Aitken streets and Watling streets are, 

 compared to these, thirrgs of yesterday. 



How is the knowledj^e of the chart passed on, with- 

 out fault or break, from jjeneration to j^eneration? 

 If old birds led the way the matter would be less 

 incomprehensible. But, writes Herr Gatke, as " the 

 incontestable result " of fifty years' watch in Heligo- 

 land : — 



" under normal conditions, the autumn migration is 

 initiated by the young birds from about six or eight weeks 

 fter leaving the nest. 



" The parents of these young individuals," he adds, " do 

 not follow until one or two months later " ! 



How and under what physical conditions are the 

 journeys made? 



Mr. Pycraft is a writer to whom ornithologists 

 already owe much, and from whom they confidently 

 look for more. His views will always carry weight, 

 but they may change. Just now he thinks it "hardly 

 necessary to attempt to bring rebutting evidence " 

 to confute Herr Gatke 's closely-reasoned argument 

 that migration flights must be made at speeds which, 



" Through the mists and vapours. 

 Amid these earthly damps," 



may well seem incredible ; but, with atmospheric re- 

 sistance removed, need seem no longer so. 



The veteran ornithologist's dream of " the existence 

 of a special respiratory mechanism, enabling birds 

 to remain in strata of the atmosphere beyond the 

 reach of all other organised beings," may yet prove 

 true. There are things more improbable. Then we 

 shall think nothing- of flig-hts at a speed of "a 

 hundred and eighty miles an hour." 



" -Airy navies grappling in the central blue " 



Bnot many months ago seemed impossibilities. Now 

 they seem uncomfortable probabilities. 



These are a few only of the questions which have 

 yet to be answered before we can hope to understand 

 what the migration of birds means. The answers are 

 not likely to be given in the lifetime of our genera- 

 tion, if ever.. It is only by the patient collation of 

 trustworthy observations, spread over a long series 

 of years, that any general conclusions can be hoped 

 for. We may sow, but others must reap. 



A modest and unpretending little volume, latelv 

 published. "Ornithological Notes from a South 

 London Suburb, 1874-1909," by Mr. F. D. Power, is 

 a useful contribution to the general stock of know- 

 ledge of a fascinating subject. The first chapters of 

 the book, well worth publication though they are, 

 will appeal rather to local than to general readers. 



It is interesting to know what birds are to be 

 looked for in one's own neighbourhood, and where 

 and when thev have been seen there. But there is 

 not rnuch to be said of thrushes and tits in Surrey 

 or Middlesex which is not to be noted as well in 

 other counties. 



There is the usual sad tale to tell — and it is very 

 well told — of wild life crowded out by growing human 

 populations. 



The lake in Dulwich Park, for instance, was once, 

 Mr. Power writes, a favourite resting-place for pass- 

 ing ducks. He has seen "on and about this com- 

 paratively small sheet of water seven species not 

 observed elsewhere in the district. In one day in 

 October, 1898, there were five scaups and four 

 shovellers on the lake, and the tufted duck nested on 

 the island for three or four years." The common 

 sandpiper was a regular visitor, and the kingfisher not 

 Uncommon. Boats have been placed on the water, 

 and " the saddened bird-lover has now little chance of 

 even an early morning note of extra interest." 

 NO. 2 141, VOL. 85] 



On Mitcham Common, once a favourite nesting- 

 place of many small birds, golf balls have taken the 

 place of eggs. 



It is in the "Migration Notes," and more esf)ecially 

 in a broadsheet table printed at the end, that the chief 

 interest of the volume for ornithologists living beyond 

 the "South London Suburb" will be found, and a 

 very real interest it is. 



Mr. Power has, during a long succession of autumn 

 migrations, kept careful records of the forces and 

 direction of the wind and of the size and direction 

 of the flifi^^hts passing within sight of his garden. 

 In a simple and admirably clear chart, the results of 

 his observations are shown for every day, without a 

 single gap, for the month of October for twenty- 

 five years. 



The rather surprising conclusions to which his 

 observations have led him would seem to find at least 

 prima facie justification in the facts tabulated. He 

 sums up as follows : — 



It used to be supposed, and by many the idea is still 

 held, that birds come and go with wind favouring them. 

 . . . My observations during these many years have con- 

 vinced me that migrants travel best and by choice against 

 the wind. . . . My experience is [he is speaking of the 

 autumnal migration] that the only visible and sustained 

 migration in numbers is invariably in a N.W., VV., or 

 S.W. direction almost directly against the wind, even 

 when such approaches a stiff breeze, the birds in their 

 progress meeting the wind on the right or left breast." 



The italics are Mr. Power's, 



The photograph otf " the garden from which the 

 migration notes were taken " does not, certainly, 

 suergest exceptionally favourable opportunities, 



His little book, like Alphonse Kerr's delightful 

 "Voyage autour de mon jardin," shows how much is 

 to be seen by "the observing eve" without going far 

 from home. T. Digby Pigott. 



NEW DISCOVERIES AT KNOSSOS. 

 /^N September 16 a letter appeared in the Times 

 ^-^ from Dr. Arthur Evans, describing the results 

 of his excavations this year at Knossos. All 

 archaeologists will congratulate themselves on the fact 

 that Dr. Evans has passed out of the path of politics, 

 which he had essaved to tread, back into the more 

 peaceful (?) ways of archaeology. For there were 

 many more things that we wanted to know about 

 Knossos, and one of them has been made clear by 

 the work of this season. The great domed pit. the 

 tholos, as it seemed to be, over which part of the 

 southern quarter of the palace was built, has been 

 excavated to the bottom, not without danger to the 

 workmen. .\nd it turns out to be a great f/ioZos-like 

 reservoir, with a spiral staircase round the inside of 

 it, which breaks off, as in other similar cases, at what 

 must have been the average water-level. The springs 

 that supplied this reservoir are now dry, and no doubt 

 were so before the place was entirely filled up. This 

 was done, as we know from the character of the 

 potsherds found in it, in the first " Middle Minoan " 

 age. 



" In other words the reservoir itself belonged to the 

 Early Minoan Age, and was filled in at the time of the 

 construction of the first Palace of which we have any 

 existing remains — the object of the work being to obtain 

 a secure foundation for the South Porch and adjoining 

 parts of the outer wall. The filling materials themselves 

 were probably supplied by the levelling away at this time 

 of the summit of the ' Tell ' of Knossos in order to gain 

 the area for the Central Court of the Palace." There 

 was also a smaller reservoir on another part of the mound, 

 " and from the magnitude of the work we may well 

 conclude that some earlier predecessor of the Great Palace 

 already existed on the site that it has since occupied." 



