AprIL 25, 1912] 
NATURE 
201 
Amongst these are what appear to be absorption 
lines, but, judging from other regions of the spectrum, 
the bright lines are the authentic ones, and the 
apparent absorption lines are more likely to be inter- 
spaces between bright lines, and have little or ,no 
significance as spectrum lines, 
The well-known series of bright nova lines on the 
less refrangible side of HB at Adqg24, 5018, 5169, 
5276, 5317, seen in Nova Persei and Nova Aurigz, are 
not well shown in the Madrid spectra, only the first 
two of these being faintly seen. This is probably due 
to the plates used by Iniguez being not very sensitive 
to this part of the spectrum, and not due to any real 
lack of lines in the spectrum. 
These bright lines and those previously mentioned 
between Hy and Hé (AA4176, 4233, 4300) were recorded 
by Sir Norman Lockyer in a series of Royal Society 
papers on Nova Persei in 1902, s being due Eek the 
i 4173 5\ 4523-2 J 429971, 
iron AA 41790) 422 3) 1 4303°3 
49241, 50186, 51692, 52762, 5316'5. These are the 
only enhanced lines of iron in the two regions men- 
tioned, and they are all represented by strongly 
marked lines in « Cygni. A direct comparison of the 
a Cygni spectrum with that of Nova Persei will show 
that these isolated strong lines of « Cygni fall exactly 
on the middles of the broad, bright nova lines. 
Some of the lines mentioned have, in previous pub- 
lications on novz spectra, been ascribed to various 
origins. The 4924 and Asor8 lines have often been 
referred to as helium lines, although much stronger 
lines of the same element have been lacking. ‘The 
line A5018 is also sometimes identified with the chief 
nebular line. The line A5169 is often referred to as 
being probably the ‘‘b” group of magnesium, and 
the line A5316°9 as being probably the chief corona 
line. The fact that all these lines occur together as 
strong lines in the spectrum of a normal star—a Cygni 
—and that they can all be adequately accounted for 
by specially behaved lines of one chemical element— 
and those the only special lines of that element in the 
region discussed—must surely be taken as convincing 
evidence that the identity is a real one. 
In the region between Hy and H&, the nova spec- 
trum is far more complex, but so also is that of 
« Cygni, and here again the chief lines in the nova 
spectrum agree in position with lines or groups of 
lines in a Cygni. In this part of the « Cygni spectrum 
there are enhanced lines of iron, magnesium, 
chromium, and titanium, but there is little or no 
doubt that in the nova spectrum the chief lines, other 
than those of hydrogen and calcium, are due to iron. 
The most striking changes between the spectrum 
of March 19 and that of March 22 are: (1) the 
occurrence of what seems to be a fine bright reversal 
in the middles of the dark Hy and H6 bands (more 
particularly the former), and (2) the appearance of a 
bright band, the centre of which is at about 4440, 
superposed on what was a broad, dark band on March 
19. One of the strongest lines in Wolf Rayet spectra 
occurs at or near this position (4442), and the two lines 
may possibly be identical. Unless, however, some of 
the other strong Wolf Rayet bands, such as AA4652, 
5692, 5813, are also found in the spectra, little weight 
can be attached to the suggested identification. 
F. E. BaxanDaLt. 
Magnitude observations of the nova are published 
in Nos. 4566-67 of the Astronomische Nachrichten, 
and Dr. Rosenberg describes his observations of the 
spectrum at the Tiibingen Observatory. On March 
19 a red-sensitive plate showed well-marked radiations 
corresponding to He, Hf, and Hy. Their breadth 
was about 30 A.U., of which 9 A.U. was shifted 
towards the red, and 21 A.U. towards the violet from 
NO. 2217, VOL. 89] 
enhanced lines of 
| present. 
the normal positions. Hy presented three maxima at 
AA4348, 4339, and 4332 respectively, and an examina— 
tion of the spectrum for polarisation effects gave a 
negative result. 
In a report to the Harvard College Observatory 
Prof. Frost states that a spectrogram taken on March 
15 shows the H and K lines bright, at about their 
normal positions; they are strong and broad and 
crossed by very sharp, dark lines. The lines at 
44923 and As5016, which Prof. Frost ascribes to 
helium, are strong, both bright and dark, but the 
line at A4472 is not conspicuous, although probably 
Witu1am E. Rorsron. 
LAE LOSSNOR LAE, “PL TANG: 
HE terrible loss of life on account of the disaster 
to the Titanic has directed emphatic attention 
to various aspects of the employment of wireless tele- 
graphy in times of crisis at sea. The point which 
is at the moment attracting most of the public 
attention is that of the erroneous messages, or alleged 
messages, which appeared in the newspapers in the 
day or two following the disaster. Possibly some of 
these messages may have been invented by 
imaginative reporters, but others seem to have been 
perversions of messages which had actually passed 
between vessels at sea, but which were not concerned 
with the accident. This kind of mistake is well 
illustrated by the transformation undergone by a 
message containing the words, ‘‘Am towing oil-tank 
to Halifax.” Such mistakes as these are possible 
in all kinds of telegraphy, but they probably arose 
in the present case at the hands of some of the 
amateur wireless telegraphists that swarm on the 
American coast. Some of these amateurs, it is: 
widely believed, may indeed have originated of set 
purpose a number of the early reassuring messages, 
and it is clear that the possibility of rigging the 
insurance market by such messages affords motive 
enough for their concoction. It is most unlikely 
that intelligence of this character should have been 
sent in irresponsible moments by operators on liners, 
for the operators are under the direct control of the 
captains, the service discipline is strict, and every 
message has to be recorded. 
All this raises more prominently than ever the 
chaotic condition of wireless telegraphy in the United 
States. For years the legitimate users of wireless 
telegraphy have complained of the unbounded 
freedom enjoyed and abused by the American 
amateur; perhaps they may now look forward to the 
imposition of some salutary restrictions. But besides 
that aspect of the matter just discussed, there is 
another which this catastrophe has brought into 
prominence. It is now impressed on us that the 
most urgent call for help will pass unheeded if none 
of the operators on the ships within hail are on duty. 
In fact, it seems to have been a mere chance that the 
Carpathia operator was at his apparatus at the time 
the Titanic called. On ships that carry only one 
operator—and very few carry more—the man cannot 
always be on the look-out. For this deadly con- 
tingency one obvious remedy is for each ship to carry 
more operators; another remedy lies in the provision 
of an apparatus that will ring up the telegraphist 
when a message reaches it. This latter desideratum 
is, unhappily, as yet unattained. 
Engineering aspects of the disaster are discussed 
in the leading article in Engineering for April 19. 
As but little definite information is available as yet, 
the drawing of conclusions is premature, but several 
questions present themselves as ripe for discussion 
and settlement. The effect of centre-line or longi- 
tudinal wing bulkheads is one of these Such have 
