Astronomy. 8335 
3. Photograph of the os trum 
of the eae Nebula in Orion ; by 
WitiiAM Huaeins. (Comatn uni- 
cated be the Author.) —On Tuesday 
cht, 7th March, I obtained a pho- 
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and special arrangements attached 
to the Cassegrain telescope of 18 
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photographie spectra of the stars. 
My former researches showed that 
in “che visible spectrum of the gas- 
eous nebule four bright lines can 
be seen. The strongest, coincident 
with the less refrangible component 
of the brightest double line of the 
nitrogen spectrum, has a waye- 
length 5005. The next line is at 
A. 4957. The other two lines coin- 
cide with Hf (F) and Hy of the 
hydrogen spectrum. 
On the photographic plate these 
four lines can be seen, but in addi- 
tion there is a strc ong line in the 
ultra-violet at the position of A 3730, 
or very nearly so, as the wide slit 
does not permit of quite the same 
high degree of accuracy of measure- 
ment as was possible in the case of 
the spectra of the stars. 
It is very probable that this new 
ane coincides with the line £ in the 
typical spectrum, as shown by my 
photogr aphs, of the brightest white 
stars. For the convenience of com- 
parison I have placed this typical 
spectrum by the side of the spec- 
trum of the nebula. I could not be 
certain if any faint lines are present 
between Hy and the new line at 
A 3730, and also beyond this line. 
I hope by longer exposures and 
more sensitive pl: ites to obtain i in- 
form: rue on these points 
The vas a faint continuous 
spe baloney on the plate, which was 
eobabiy due to stellar light. The bright stars of the Tra- 
