January 9, 1896] 



NATURE 



223 



The Habits of the Cuckoo. 



In connection with the interesting article in Nature of 

 Dec. 26, 1895, on the habits of the common cuckoo, it maybe of 

 interest to some of your readers to record the following observa- 

 tions, which afford further evidence in support of the contention 

 that the cuckoo occasionally lays its egg before carrjing it to 

 the nest in which it is to be deposited. 



A few seasons ago, a pair of robins built in the ivy covering the 

 walls of our house. It was cunningly concealed, about five feet 

 from the ground, in a hollow formed between the wall and the 

 interlacing stems of the ivy. The nest was successfully finished, 

 and four or five eggs were laid. One day, in the early hours of 

 the afternoon, the loud notes of a female cuckoo attracted our 

 attention. Almost immediately afterwards we saw the bird on 

 one of the branches of a large yew-tree growing close to the 

 corner of the house where the nest, was placed, and one of our 

 ])arty exclaimed, " Oh ! it is holding something in its beak." It 

 seemed in no way disturbed by the close proximity of the house 

 and its inhabitants, and, after a moment's pause, flew down and 

 disappeared behind the angle of the wall. It then quickly re- 

 apjjeared and flew away, making a considerable noise. We im- 

 mediately went to the nest, and found the cuckoo's egg together 

 with the robin's. The entrance to the robin's nest, and the 

 entire hollow where it lay, was far too small to admit so large a 

 bird as the cuckoo ; the short time, also, that the bird was there, 

 presumably points to the fact that it carried its egg thither and 

 simply placed it in the nest. 



Some years before, much the same thing occurred in the same 

 garden. In this instance the robin's nest was in a hole in a bank, 

 which was also too small to easily admit the cuckoo. The parent 

 robins were seen furiously attacking the larger bird, who was 

 forced to beat a retreat. But it had already deposited its egg in 

 the robin's nest, where we found it immediately afterwards. 



London, December 29, 1895. Annie Ley. 



A Luminous Centipede. 



Was not the insect seen by Miss Rose Haig Thomas (see 

 Nature, p. 131) a specimen of the Myriapod Scolopendra 

 ikctrica, or Geophilus eleciricus, a well-known luminous 

 insect whose light is but rarely seen owing to the insect 

 living underground and in manure heaps? It is, however, 

 the only luminous British species. I have but once seen one 

 crawling abroad at night, but I know the insect well. It 

 may be readily captured in the daytime. The light is bright 

 and the colour is the same as that of the glow-worm. Accord- 

 ing to my observation both sexes are luminous, and the light 

 is not peculiar to the summer season, as is that of the British 

 glow-worm, hence the meeting of the sexes can scarcely be the 

 object of the luminous prevision. 



Worcester, December 20, 1895. J- Lloyd Bozvvard. 



It is impossible to give an unqualified reply in the negative to 

 Mr. Lloyd Boz ward's question ; but for reasons stated in the note 

 a])pended to Miss Rose Haig Thomas's communication, I see no 

 grounds for doubting that the specimen she observed was an 

 example of Linolania crassipes, and not of Geophilus electricus 

 ( = Scolopendra electrica, Linn.). So far as my experience goes, 

 the latter is very scarce in the south of England. It must be 

 borne in mind, however, that there is no safety in the assump- 

 tion that every luminous centipede found in this country is 

 certainly referable either to one or the other of these two 

 si^ecies. As a matter of fact, the family Geophilida is repre- 

 sented in England by at least a dozen species, belonging to five 

 genera, and it is possible that all of them possess the property 

 i)f phosphorescence. Perhaps it is not surprising that persons 

 unaccjuainted with these facts jump to the conclusion that every 

 luminous centipede they see must be co-specific with the one to 

 which Linnaeus gave the name electricus. This is so far from 

 being the case, that not one of the many specimens that have 

 been brought of late years to the British Museum, on account of 

 its luminosity, has proved to be an example of this species. No 

 doubt, however, there is much that might be learnt on this sub- 

 ject by the careful preservation of specimens, with particulars as 

 to date, locality, &c., and I need hardly add that I shall be 

 very pleased to identify any examples that are sent or brought 

 to me at the British Museum for that purpose. 



British Museum, Cromwell Road, S.W. R. I. PococK. 



NO. 1367, VOL. 53] 



A Lecture Experiment on the Nodes of a Bell, 

 The following modification of Chladni's method makes an 

 interesting lecture experiment, and shows the nodal lines of a 

 bell far more sharply and easily than any process already de- 

 scribed of which I am aware. For the bell, use a cylindrical 

 glass crystallising pan (say nine or ten inches diameter and four to 

 six inches deep, but almost any size will do), and stand it, rim 

 upwards, on three india-rubber corks. Some light-coloured 

 powder, such as flowers of sulphur, is mixed with soapy water 

 and smeared over the concave surface. The mixture should be 

 quite watery, and can be applied by pouring a little into the bell, 

 which is then tilted as much as possible and rotated round its 

 axis. With one hand inside the bell, press it down firmly on the 

 corks, and excite the rim with a bow. It is best to make double 

 contact with the bow at two opposite points on the rim, and a 

 succession of rapid strokes will produce strong vibrations, the 

 powder meanwhile shooting upwards in arch-like curves, till it 

 collects in four or six distinct vertical lines, easily visible at a 

 distance if held against something black. Using a smaller 

 vessel, smeared only half-way round, no doubt the whole process 

 could be optically projected. G. Osborn. 



The I^ys School. Cambridge. 



The Critical Temperature of Hydrogen. 



Ii" my allusion to the absence of " fresh experiments " in Dr. 

 Natanson's work is not sufficient acknowledgment of its purely 

 theoretical nature, a reference to my original abstract in the 

 Physical Society's Proceedings will, I feel sure, correct any false 

 impression that has arisen in the author's mind on that point. 

 My note was in no way intended as a criticism or expression of 

 opinion.} But the Cracow Bulletin paper was certainly calcu- 

 lated to give any reader the idea that Dr. Natanson was the 

 only worker besides Olszewski who had attempted to calculate 

 the critical temperature of hydrogen, and, to prevent misunder- 

 standing, a reference to Wroblewski's previous work seemed 

 desirable. As Dr. Natanson still appears to pass over the long and 

 laborious experiments on which the latter investigation was based, 

 and to be unaware that the whole object was to get the critica4 

 constants, &c., from the application of Van der Waals^ theory 

 (which had previously given chemists an accurate knowledge of 

 such data in the case of oxygen, nitrogen, and marsh-gas before 

 the gases had been actually li(/tiefied), I must refer him to Wrob- 

 lewski's memoir. Further, it might interest him to consult a 

 paper by Prof. Dewar in the Philosophical Magazine for Sept- 

 ember, 1884, which discusses the critical constant.e of hydrogen 

 based on the experimental facts known at that time. 



G. H. Bryan. 



THE SPERM WHALE AND ITS FOOD. 

 HTHE services which H.S.H. the Prince of Monaco- 

 -*■ has rendered to the science of oceanography, during 

 the last ten or twelve years, are familiar to every one 

 interested in that department of research. First in the 

 small schooner Hirondelle, with no power but the strong 

 arms of his Breton crew, and later, in the large and 

 perfectly equipped auxiliary steam yacht Princesse Alice, 

 there is no branch of the science which has not been 

 enriched by his enlightened enterprise and his unwearied 

 perseverance. It may be interesting to the readers of 

 Nature to know something of what was achieved in the 

 summer cruise of 1895 in the waters of the North 

 Atlantic, chiefly in the vicinity of the Azores. The 

 dredging and other deep-sea operations conducted on 

 board the yacht herself were very successful, and produced 

 an abundant harvest. The most interesting result of the 

 cruise, however, was due to the lucky chance of a 

 cachalot or sperm whale being pursued by the whale- 

 fishers of Terceira, and killed almost under the bows of 

 the Princesse Alice, and to the prompt measures taken 

 by the Prince to utilise this rare opportunity, the im- 

 portance of which for science he immediately and 

 mtuitively perceived. The preliminary reports of the 

 investigation of the material thus collected by the Prince, 

 in collaboration with the Portuguese whalers, go to show 



