March 13, 1913] 



NATURE 



Identical. The numbers we used were by Watson, 

 and both spectra were measured from plates produced 

 bv the same instrument, and, of course, measured by 

 the same person ; thus experimental error was 

 eliminated so far as possible. We were, however, in 

 hope that possibly some similarity in atomic com- 

 plexity might be argued from this "parallelism." 

 But on talking the matter over with Prof. Fowler, 

 whose knowledge of the subject is far greater than 

 ours, we see that the evidence is not sufficient to 

 justify any such assumption of similarity in the 

 atomic complexity of these two elements, and we 

 must therefore with regret abandon the idea. 



J. Norman Collie. 



Hubert S. Patterson. 



Mountain Stream Tadpoles in Natal. 



Some readers of Nature will be interested to learn 

 that tadpoles with large suctorial oral discs, enabling 

 their possessors to adhere firmly to the rocks and 

 boulders of mountain streams, have recently been dis- 

 covered at Krantzkloop, in Natal, at an elevation of 

 about 1500 to 1600 ft. They were found by the Rev. 

 Fr. P. Boneberg, of Mariannhill, who kept them 

 alive for some time, and observed their peculiar leech- 

 like habit of sticking to one's fingers or to the sides 

 of the vessel in which they were contained. Similar 

 tadpoles have long been known from mountain streams 

 in Borneo and other parts of the East, but so far as 

 I can ascertain have not previously been recorded from 

 Africa. However, the Natal tadpole belongs to the 

 family Cystignathida; (genus Heleophryne), whereas 

 those of the Oriental region belong to the family 

 Ranidae. so that the adaptations are no doubt quite 

 independently evolved. A description of this tadpole 

 will be given in the next issue of the Annals of the 

 Natal Museum. John Hewitt. 



Albany Museum, Grahamstown, South Africa, 

 February i. 



[In his recently published account of the Batrachia 

 of the Abor expedition, Dr. Nelson Annandale directs 

 attention to some of the tadpoles (from Himalayan 

 streams) which adhere to stones at the bottom or 

 sides, and even in the vicinity of waterfalls. The 

 majority adhere by their lips, which may be mon- 

 strously developed. In some other species a sucker, 

 quiti separate from the lips, and not homologous 

 with the sucker that many young Batrachian larvae 

 possess, is found on the ventral surface, doubtless for 

 the same purpose. It is interesting to note that some 

 fishes have similar adaptations for adhesion. — Ed. 

 Nature.] 



INTERNATIONAL TIME AND WEATHER 

 RADIO-TELEGRAPHIC SIGNALS. 



IT is to the French Government that the world 

 is indebted for the institution of an inter- 

 national conference on the radio-telegraphic dis- 

 tribution of time and weather signals. So long 

 ago as 1908 the Bureau des Longitudes suggested 

 a series of hourly signals from the Eiffel Tower 

 for the determination of longitudes, and this ser- 

 vice was brought into active operation in 1910. 

 The great success which the service met with 

 called for a more universal use of it, and to this 

 end the French Government invited a certain 

 number of foreign Governments to send delegates 

 who had studied the problem of radio-telegraphy 

 from the point of view of time and the determina- 

 tion of longitudes. 



NO. 2263, VOL. 91] 



In October of last year such a conference was 

 assembled, and programmes were formulated and 

 resolutions passed with the object of preparing the 

 way for the distribution of time and weather 

 signals at stated hours from numerous selected 

 stations suitably situated over the globe. 



The outcome of this, the first international con- 

 ference convened for this purpose, was a series of 

 very important resolutions, but reference will only 

 be made here to those that deal with the inter- 

 national time and weather signals. It may be of 

 interest briefly to describe in the first instance 

 samples of two signals that are being daily dis- 

 tributed at the present time, in order that the 

 reader may compare them with the full inter- 

 national system which will be brought into opera- 

 tion on July 1 next. 



Our purpose will be served if those sent out 

 from the Eiffel Tower, Paris, and from Norddeich- 

 Wilhelmshaven be alone considered, as these will 

 show the different procedures adopted. To take 

 the French signals first as recorded by a receiver 

 in London. From this station morning and even- 

 ing signals are transmitted, and at each trans- 

 mission three separate " minute " signals are sent. 

 Thus in the morning the observer can hear the 

 tap from the pendulum clock in Paris at 

 ioh. 45m. os., loh. 47m. os., and ioh. 49m. os., 

 and in the evening at 23b. 45m. os., 23b. 47m. os., 

 and 23I1. 49m. os., the clock indicating Greenwich 

 mean time. In order to warn those who intend to 

 receive the signals wherever they may be, a cer- 

 tain procedure is adopted which is the same for 

 both morning and evening transmissions. This 

 procedure is as follows : — 



Let us suppose that we wish to correct our 

 watch and therefore require to hear the morning 

 signals. At about ioh. 40m. one sits by the 

 receiving apparatus with the telephone fixed on 

 the head, the coils set for the wave-length in use 

 (about 2000 metres) and the detector adjusted, and 

 waits for the preliminary signals. It may be 

 mentioned here that the noise heard is of a power- 

 ful medium note, and the operator transmits the 

 individual signals quite slowly so that they are 

 easy to decipher. 



The first sounds to be heard are the signal 



ta-te-ta-te-ta ( repeated three times, which 



is a "call" signal in Morse preliminary to every 



transmission. Then follows , which means 



(=), a signal to separate the "call" from that 

 which follows. The operator transmitting then 

 sends out the following in Morse : — 



'~P~' "A r' I S li s e r v a 



(double dash) 



The last four signals indicate "wait," repeated 

 four times. 



