THE ‘ GEM” CLUSTER IN ARGO. 31 
34:58”. Inthe — all the stars determined by putting them 
in the map, and then measuring their places, have been marked E, 
to indicate that the position is estimated in the way described. 
A few words about the way this map has been printed may not 
be out of place here, since this is the first star map that I have 
prepared in this way. Some at least of the members present will 
remember that, at a recent meeting of the Astronomical Section I 
described a process by means 0 which any astronomical observer, 
with very little more trouble than is required to make a drawing 
of his work upon paper, may produce a block from which he can 
print as many copies as he requires. The process is not altogether 
new ; engravings are frequently made in type metal, but by the 
hands of trained engravers. I found that any lines marked on the 
type metal or holes made into it, even with fine needle points, would 
print white, or more correctly, not print at all. For the reference 
lines then, I grea mee them as I would wenn paper, using a steel 
a Ss 
upon the block are ones punched in, and the words at the side 
are engraved. have thus been able to produce a map which it 
bee: 
to draw it on paper and watch it through the engraver’s hands. I 
consider this process of considerable importance to astronomers, 
because they will now be able to represent what they see without 
having the life filtered out of it by the engraver, simply because he 
cannot be made to understand what he has never seen. 
CATALOGUE OF STARS IN THE ‘‘GEM” CLUSTER. 
List of Stars in A quadrant. 
be Mag. ee nit hen sta Remarks. 
at-12 20°7 7°74 8. 4 
mt Ae 36°66 | 
st 16 118 4214 | Micrometer 4222 42°06 
4| 15 | E34 47-00 
or mH 1B 335 74°00 
es Se 6°7 85°85 ss 85°70 85°92 
7} 104 be aa | 103°26 
me es 117°33 
Pe Wee) 79 182° a 133-24 131°60 
10| 14 E 160 188-00 
Hy} 13 | E 30|- 195-00 : 
All marked E not measured with micrometer. Total, 144 stars. 
