14 
THE YOUNG SCIENTIST. 
sidered to be the grandest of the constellations, 
and the observer will be well repaid for careful 
observation. It has fewer Nebular objects than 
Ursa Major, but grander, and it contains such a 
vast number of bright and double stars, and 
clusters, that it affords a far richer field for the 
astronomical observer. It contains two stars of 
the 1st mag,, four of the 2nd, and three of the 
3d. The great nebula and the trapezium have 
already been described and figured in the 
Young Scientist for March, 1879, p. 46. 
Betelguese is the most brilliant star, being, 
when brightest (it is an irregular variable), the 
" largest star in the northern hemisphere." 
Lasell says of it: "A rich topaz, in hue and 
brilliancy differing from anything I have ever 
seen." It is double ; companion 9th mag., 160'' 
distant. A line from Betelguese through the 
belt, continued nearly as far again, will reach 
Eigel, a double, and the brightest star below the 
belt, and one which will severely test the ob- 
server's telescope, if small. The companion is 
of the 9th mag. and distant 9' .5 ; its combined 
closeness and sraallness reader it difficult, l3ut 
it has been separated with an aperture as low 
as 2| inches— we have seen it with a 3-inch 
achromatic — companion, blue. 
Very close to the lowermost star in the belt 
( V^ west, and a trifle lower) is a bright white 
star of the 4th mag. This is a fine multiple 
star — a double triplet, with two fine stars be- 
tween the sets, and easily found. Fifteen stars 
have been counted in this group— eight with a 
good 3-inch glass. This is a most interesting 
object, even when very small telescopes are 
used, and it also forms a good test-object for 
distinction. O^lor of companions : bright white, 
ash-colored, bluish, grape-red, dusky, Avhite, 
and pale-grey. 
We have not yet told the half of the richness 
of this constellation, but must close. 
Jupiter is too near the sun to admit of satis- 
factory observation of the phenomena of his 
satellites.- % 
Penn Yan, N. Y. 
Finishing- and Polishing Brass. 
Many who hear the words " brass finisher " 
may be led to believe that this would apply to 
those who produce highly-finished work ; but it 
is not so, the brass finishers in reality are not 
the superior class of workmen supposed, the 
work most of them do is comprised in gas- 
fittings, ormolu mounts, etc. ; but the high class 
of brass finishing is a totally different process. 
We will take several examples : First, say fit- 
tings for gas work, all well-enough finished for 
their several purposes, and quite as well done 
as the price paid for them will allow. Then we> 
come to the mountings for furniture ; these must 
obviously be produced at a low price, in order to 
supply the demand for cheap things of this 
character. We will now pass on to a totally 
different class of work— for instance, micro- 
scopic and philosophical instruments. These 
are most beautifully finished, and must also 
be made in a superior manner, before any at- 
tempt can be made to finish them; also the 
beautiful parts that are now made to the turn- 
ing lathes of the present day. As this particular 
branch affords scope for the explanation of 
really good brass finishing, we will take a few 
parts of the lathe and its various appurtenances. 
I In malving an eccentric chuck, a deal of high- 
' class work will be required. We cannot call a 
' piece of work well finished that is simply very 
I bright, but full of scratches. High polish and 
! deep scratch must at all risks be avoided, as the 
j latter are a sign of indift'erence on the part of 
the workmen. To begin, or rather before com- 
I mencing to finish and polish, all marks of the 
I file must be removed, and this is done thus : 
Having used a superfine Lancashire file to draw 
! the edges and file the surfaces, take a piece of 
I moderatply fine emery paper and wrap it tightly 
round the file, onl.y once round. It is by having 
so many folds round the file that the work be- 
comes rounded off at the edges, and made to 
look like second-hand things that have been 
cleaned up several times. Some workmen use 
emery sticks ; they are made by having several 
pieces of wood planed up, about i inch thick and 
I inch wide, quite flat on the surfaces. This 
done, they are covered with a solution of thin 
glue, and the emery powdered on to them, and 
then allowed to dry hard. Most of the common 
work is, I will not say finished, but rubbed over 
with emery cloth. This is all well and good for 
such purposes, but it will not do for good work. 
Having folded the paper once round the file, it 
is worked in a similar manner to the file, and 
j when the file marks disappear, and the paper is 
I well worn, a little oil should be used with it, as 
I this fills up the paper and makes it cut smoother. 
I Having got up the edges and surfaces to this 
I extent, to finish the edges must be the first 
thing, and the best way to effect this is to have 
a piece of soft wood, quite flat, and rub on its 
surface a little oilstone powder, free from grit. 
Now, the best way to be sure of having it quite 
clean is to have a piece of old Turkey-stone by 
you, and as you want to use it break a small 
piece off and pound it on the corner of a surface,, 
or anything equally hard. You will then be- 
sure that it is quite clean. It is exceedingly an- 
noying to make a deep mark in the work just as- 
it is finished, perhaps a mark that will require^ 
