

stamp, I will send a drawing so he can 
easily make one. 
Raymond W. Pinkerton, Elgin, Ill. 

The photographic department of RECREA- 
TION is interesting and I should like to see 
more space given to it. Have recently 
bought a 5 x 7 camera, fitted with a Uni- 
cum shutter marked with the speed values 
one second, 1-2, I-5; I-25 and 1-100 second. 
Wishing to use other speeds I constructed 
the following curve, or speed diagram, 
which may be of interest to others ‘using 
the Unicum shutter. 
From a point on a horizontal line lay 
off the distance from the one second. Mark 
on the shutter to the 1-2 sec. mark; to the 
1-5 sec. mark, etc. These distances may 
be measured by dividers, as the chord ap- 
proximately equals the corresponding arc. 
Through these points on the horizontal! line 
draw verticals. On the vertical at a lay 
off any convenient distance, as 5 inches. 
On the next, or I-2 sec. line lay off 1-2 of 
5 inches; on the 1-5 sec. line lay off 1-5 of 
5”, etc. Then through these points draw 
a curve. 
To find the point at which the speed indi- 
cator must be set for say 3-4 sec., measure 
up from a 3-4 of 5”, or whatever length is 
taken for a-1, and draw a horizontal line 
through this point c to the curve at cl. 
Then the distance c-c, measured from the 
I sec.mark on the shutter, gives the indi- 
cator position for 3-4 sec. Any required 
speed can be obtained in the same way, al 
ways measuring to the vertical next on the 
right. The shorter a-1 is, the less ac- 
curate the result. 
H. C. Thompson, C. E., Cohoes, N. Y. 

The photo department of RECREATION 
has been permanently enlarged to 4 pages 
and now if the amateurs will do their part 
I shall soon be able to enlarge it still more. 
Every reader knows that the success of a 
AMATEUR PHOTOGRAPHY. 77 
magazine nowadays depends upon its adver- 
tising patronage. It costs me more than 
a dollar a year to print and mail RECREA- 
TION to each of my subscribers. I even 
lose money on every copy sold on the news 
stands. I must recoupe on the advertising 
pages, if at all. The same may be said of 
almost every magazine published in this 
country. 
There are many good cameras, lenses, 
shutters, plates and print papers that are 
not yet advertised in RECREATION, and that 
if made known to my readers would enjoy 
much larger sales than now. In _ other 
words, it would pay makers to use this 
magazine. However, they do not know it 
and amateur photographers who read 
REcREATION could aid me greatly in en- 
lightening them on this subject. When 
you write any such houses, on business of 
any kind, tell them what they are losing 
by not being represented in RECREATION. 

Thus you will confer a lasting favor on me, 
- and as fast as new business materializes 1 
can still further extend and improve the 
photo department. 
Furthermore, readers should contribute 
to this department just as hunters and fish- 
ermen do to the other departments in 
RECREATION. I am overstocked with mat- 
ter for these other departments all the time, 
and have to hold a good deal that comes 
to me 4 to 6 months before I can find 
room for it; but in order to fill the 2 pages 
I have been devoting to this department, I 
have had-to clip freely from exchanges. 
Every amateur runs against items, wrinkles, 
kinks, snags and ideas every month that 
would furnish valuable food for thought if 
written down and published. Let us have 
an avalanche of them during the next year. 

It is sometimes desirable to dry a newly 
developed negative quicker than usual. The 
application of heat is nearly always at- 
tended with shrinking and breaking of the 
untreated film, as nearly all amateurs caa 
