266 



NATURE 



\ytdy 17, 1879 



may be allowed to point out that the fact mentioned by Prof. 

 Virchow favours rather than disproves this view. If the plain 

 between Hissarlili and the sea has been gradually formed by the 

 detritus brought down by Scamander the materials would be of 

 fresh-water origin. The observations made by Dr. Virchow 

 appear therefore to me by no means to bear out the conclusions 

 which it is said have been drawn from them. 

 15, Lombard Street, E.C., July 12 John Lubbock 



On the Origin of Certain Granitoid Rocks 



Dr. Hicks has very properly called attention to his prior 

 discovery of the transitional nature of some halleflintas, and I 

 regret that I overlooked this point in his valuable papers on the 

 Pembrokeshire rocks. I may, however, be permitted to point 

 out that my observations in Shropshire go further than those of 

 Dr. Hicks, since the halleflinta observed in the Wrekiu range 

 passes not merely into "incipient gneiss, the metamorphic 

 action being incomplete, a kind of semi-metamorphism and 

 softening having taken place, etc." ; but into a true gneiss, 

 distinctly foliated in bands of quartz, felspar, mica, and some- 

 times hornblende, and into granitoidite and granite. In the 

 Wrekin we see the completion of the change of which Dr. 

 Hicks recorded the earlier stages. C. CALLAWAY 



Wellington, Salop, July 12 



The Telephone 



Experiments that I have recently made with a "Bell" 

 telephone have convinced me that the sounds produced are the 

 result of molecular change in the iron disk, and are the same in 

 kind as those heard in the telephone of Reiss. 



My experiments were made with a carbon transmitter and 

 Bell receiver, using a small battery to generate the current. 

 First I removed the bar magnet from the receiver, in accordance 

 with a suggestion made by a writer in Nature some months 

 ago. The effect without the magnet was the same as with it. 

 It then occurred to me that the intensity of the sound might be 

 increased by using two disks instead of one. Accordingly I cut 

 two circles out of a piece of sheet iron, leaving a narrow strip 

 of the metal to connect them, of sufficient length to enable the 

 disks to lie on either side of the reel, so as to form, in fact, an 

 armature to the electro-magnet. On experimenting with this 

 my anticipations were fully realised, the sound produced being 

 more than double that from a single disk. 



Now, while trying these experiments I held the disks loosely 

 in my hand, without their being in any way fastened to the wood 

 holding the reel, the effect being the same as if firmly secured. 

 In fact, a common dinner knife or a rough piece of iron would 

 emit sound if brought near enough to the core of the electro- 

 magnet. 



I have since constructed a very efficient telephone receiver out 

 of a block of wood two inches square and three-quarters of an 

 inch thick. I then drilled a hole sufficiently large to receive the 

 reel, and covered the block with thin sheet iron. It needs no 

 ear-piece, and forms the most effective telephone receiver that 

 I have seen. But, still further to prove that the sounds pro- 

 duced are due to the magnetisation of the iron of the disk, and 

 not to mechanical vibrations resulting from the electro-magnet, 

 I made an iron reel, the flanges of which were two inches in 

 diameter. Now, on covering this reel and placing it in cir- 

 cuit, the flanges of the reel gave out sound as clearly as in the 

 Bell telephone. In my judgment this experiment renders it 

 conclusive that the sounds proceed from the magnetisation and 

 demagnetisation of the iron, and are therefore precisely the same 

 in character as those formed by a Reiss receiver. 



Percival Jenns 



St. John's Rectory, British Columbia 



Inherited Memory in Birds 



Some interesting communications liave lately appeared in 

 Nature on this subject, accounting for the wonderful knowledge 

 of routes and localities displayed by birds in their migrations, 

 by the theory that the impressions made on the brains of the 

 parents are transmitted to their offspring, and that which we call 

 vaguely instinct is often inherited memory. 



The following circumstance is hard to explain on any other 

 theory : — 



About twelve years ago I was residing on the coast of Co. 



Antrirn, at the time the telegraph wires were set up along that 

 charming road which skirts the sea for twenty-five miles between 

 Lame and Cushendall. During the winter months large flocks 

 of starlings always migrated over from Scotland, arriving in the 

 early morning. The first winter after the wires were stretched 

 along the coast I frequently found numbers of starlings lying 

 dead or wounded on the roadside, they having evidently in their 

 flight in the dusky morn struck against the telegraph wires, not 

 blown against them, as these accidents often occurred when there 

 was but little wind. I found that the peasantry had come to the 

 conclusion that these unusual deaths were due to the flash of the 

 telegraph messages, killing any starlings that happened to be 

 perched on the wires when working. 



Strange to say, that throughout the following and succeeding 

 winters hardly a death occurred among the starlirgs on their 

 arrival. It would ;thus appear that the birds were deeply im- 

 pressed and understood the cause of the fatal accidents among 

 their fellow-travellers that previous year, and hence carefully 

 avoided the telegraph wires ; not only so, but the young birds 

 must also have acquired this knowledge and perpetuated it, a 

 knowledge which they could not have acquired by experience or 

 even instinct, unless the instinct was really inherited memory 

 derived from the parents whose brains were first impressed by it. 



Sudbury, Suffolk J. Sinclair Holden 



Butterfly Swarms 



Some, at least, of the swarms of V. cardui originate in Africa, 

 one of which I witnessed a day's march west of Sowakin, in 

 Nubia, in March, 1869. Our caravan had started for the coast, 

 leaving the mountains shrouded in heavy clouds, soon after 

 daybreak. At the foot of the high country is a stretch of wiry 

 grass, beyond which lies the rainless desert as far as the sea. 

 From my camel I noticed that the whole mass of the grass 

 seemed violently agitated, although there was no wind. On 

 dismounting I found that the motion was caused by the contor- 

 tions of pups of V. cardui, which were so numerous that almost 

 every blade of grass seemed to bear one. The efiect of these 

 wrigglings was most peculiar, as if each grass stem was 

 shaken separately — as indeed was the case — instead of bending 

 regularly before a breeze. I called the attention of the late 

 J. K. Lord to the phenomenon, and we awaited the result. 

 Presently the pupae began to burst, and the red fluid that escaped 

 sprinkled the ground like a rain of blood. Myriads of butter- 

 flies limp and helpless crawled about. Presently the sun 

 shone forth, and the insects began to dry their wings ; and about 

 half-an-hour after the birth of the first, the whole swarm rose 

 as a dense cloud and flew away eastwards towards the sea. I 

 do not know how long the swarm was, but it was certainly more 

 than a mile, and its breadth exceeded a quarter of a mile. 



Sydney B. J. Skertchly 



Distribution of the Black Rat 



From Prof. Giglioli's letter in Nature, vol. xx. p. 242,'it 

 appears that the black rat is more abundant and widely dis- 

 tributed in Italy than in England. I know of some half-dozen 

 specimens having been caught from time to ti re in the city of 

 London, and in November, 1876, a male about six weeks old 

 was caught, which lived in confinement for two years and three 

 months. It was mated with a tame white one, and they had 

 two litters of young which were black, save the feet, tip of tail, 

 and a small brush of pure white upon the chest. 



Chas. Coppock 



Grosvenor Road, Higbury New Park, July 11 



Pine Pollen and Sulphur 



By a coincidence which depends upon the season of pollen- 

 discharge occurring at the same period in Scotland as in England, 

 I am enabled to send you an extract from the Haddingtonshire 

 Courier of June 27, which may serve to dissipate the " sulphur- 

 eous theories " of Mr. Carpenter's opponents. 



" The rustics in this district [Gifford] have been of late much 

 interested in a peculiar shower which had fallen in the early 

 morning of Monday last. All the pools on the roads were 

 covered and fringed with a powdery substance strongly resembling 

 the flowers of sulphur. A calculating Good Templar found 

 that the fiery powder had been drifted more about the houses of 

 those who loved the flowing bowl than those who loved the 



