Notebook of Gerard Henderson Cowan - Part 11

-The Service Prismatic Compass - 
The dial is ''luminous'' for nightwok
work, the north point is marked

with a large diamond-shaped

figure. A revolving glass is
fitted over the compass dial,
and on the glass is a black
direction mark, radiating from
the centre, at the end of which
is a small brass "setting vane,"
the latter working over an
external arc of 360^o
A brass screw, J, is used to clamp
the glass.
On the inside of the cover are
two luminous patches, PP, which
give a good alignment of the
instrument at night
when it is held in the hand
with the cover wide open.
There are two small holes, HH,
in the brass window edge
 

- The Service Prismatic Compass -
of the cover, so that, if the
glass breaks, a horse-hair can
be run between them, and
an extemporized sight vane
be utilized.
The compass dial is graduated
with two sets of figures
which read eastward from
of the meridian or from
left to right, like the hands
of a watch. The outer set
is for use with the prism,
and commences at the
South in order that the
bearing of the object may
appear under the eye.
Thus the vane being
directed on an object
which is 50^o from the
North, it is that number
from the measured
- The Service Prismatic Compass -
from the South which appears
under the prism, or in other
words 180^o is over the north and
and 360^o over the South end
of the needle.
The inner set of figures is of
use for direct readings, as
for compass marching, or
when the instrument
is used with the plane table
The Prismatic Compass gives
bearings not angles.
The horizontal angles between
any distant objects are
obtained by taking the
difference of their observed
bearings
 

- Conventional Signs -
Diagrams - see original document
- Used in Field Sketching -
Diagram - see original document
 

Tuesday 24.9.18
Weather bright & clear this morning
but clouded up during the
afternoon, clouds becoming very
low. It is now raining steadily
Did not do any flying owing
to bad weather. Was going
to do a shoot this evening
but clouds were too low.
M. Capt C, & at F. undercarriages
Attended classes in the afternoon
viz Gunnery 1 hour, buzzing 45
Heard tonight that Sergt Wilkins
of the 22/11 is a Loightethon
with the 7^TH Squadron. Must
try to get over to see him.
Wednesday 25.9.18
Weather much clearer, but bumpy
Flew the 900 up SE5 and
did a shoot. 300 rounds
100 Vickers & two magazines
of Lewes. Dives steep enough
 

but firing too high and
pulling out too soon. Had
great difficulty in keeping
onto the target owing to
a cross wind. Time 75 minutes
Thursday 26.8.18.
Weather dud. It clouded up
early this morning and
started blowing & raining
early in the day.
Was officer of the Watch from
6 AM to 9 AM.
Had to get to work & find pett
petrol & oil. for two RE8's
and an A.W. which arrived
here last night having
got off their track.
W. was flying the A.W.
he is from this Squadron
and is at present ferry-piloting.
Ten or twelve
new cadets came in last
night, consequently there
has been a bit of a crush
at meals today.
All flying washed out
owing to dud weather.
The RE86 & AW getting away
soon after breakfast, being
the only planes up from
here. Only had to attend
classes in the afternoon.
Among the Cadets to come
to 6.T.S. is Mat.S a boxer of
some repute.
Friday 27.9.18
Weather fairly good.
Could not get a machine
to fly.
Went into Stroud
and visited went to the
pictures in the evening
 

Saturday - 28.9.18
Weather still fairly good
but could not get a
buss to fly. Flying
was washed out early
owing to boxing contest
in Stroud.
Sunday 29.9.18
Weather fair early in
the morning. Started
raining about 10 AM and
has been coming down
steadily ever since
Very cold. Rain is turning
to sleet.
Was going to do another
shoot this morning
but on going to get
the buss found them
renewing the oil
Then they found the
Lewes gun was out
of action and then
before they had fixed
that they suddenly
decided that the
rigging had to be
checked as a landing
wire had been broken
A new one was put it
and then the flying
wires were found to
be slack and had
to be looked to.
By that time it was
raining too heavily
to fly. So far I have
only had one fly this
week.
I have another 700
rounds to fire, a
height test (15000) to do
and also a scrap &
 

a formation to do
before graduating.
I had hopes of doing
that before Wednesday
but if this weather
continues I will not
be able to do so.
I will then probably
get four days graduation
leave. I wrote to Gracie
last night to see if
I might stay there.
Monday 30.9.18.
No flying today.
Three flights (1 oil dud (2) Alt 16000 (3) 12000 Formation
Tuesday 1.10.18
Started flying early this
morning and did stunts
and then had a scrap
with Capt Holden
At 11-10 am flew SE5 353
135
and did a shoot - 50 minutes
Landed had the machine
refilled and more ammunition
and at 12.25 went up
again being up this time
80 minutes. Thus finishing
my 1000 rounds and
bringing my time up to
9 hours in SE58
On landing Capt Holden
told me I would have
to do a cross country
flight of a couple
of hours to bring my
time up of over the
10 hours so I could
graduate.
Had a hurried dinner
got cleaned up a bit
and then went over
to the drome
 

I started at 3.10 pm and
flew B flight bus - SE5 1924
I had decided to go to
Wendover and land
at Witney and Rendcombe
on my return journey
I flew to Oxford and then
followed the railway
to Wendover. On arrival 
there found the aerodrome
to be a small one
in amongst trees making
it rather tricky to land
in. Had three trys
before getting in. Gott
Had my machine refilled
there. They wanted me
to escort a Handley
Page machine to
the aerodrome. It was 
getting dusk, however
I told them I would
spend half an hour
looking for it and
if I could not find
it by that time would
go on. Just as I was
about to go off a
note arrived to say
that the H.P. had landed
and would not be coming
that night, so I was saved
the trouble, not sorry as
it was getting late. the
hours difference alteration in time
now makes a great
difference Left Wendover
and flew straight back
to Witney. I landed
there, by a bit of luck
made a goo posh landing
and was complemented
 

on it. Had a chit signed
here and started straight
off again. Did not call
at RendCombe as it
was too late. As I
passed over Cirencester
I could see them firing
Very lights from our
aerodrome about 7 miles
away. It was almost
dark by then so c
my landing was a bit
bumpy. On arrival
found there was another
machine out on a cross
country which has
not turned up yet.
My top actual flying
was 2½ hours bringing
my time on SE5 x to 11½ hrs
and my time for one day
to 5.45 hrs. Not bad when
you are only supposed
to do ^not more than 2 hrs each day.
Wednesday. 2.10.18
Packed my Suit case &
-     and after getting
a chit from the Adjutant
to say I had graduated
caught the 12.49 train
for London. The missing
SE5 pilot turned up
safely just before I left
He had had two forced landings
but had got on OK.
I arrived in London and
spent the afternoon at
5A Bickenhall Mansions
Put up at Officer-Cadets
Club at Regents Pa Park
a very decent place.
Thursday 3.10.18.
Spent about 3 hours
 

this morning getting
my paybook etc etc
fixed up and promotion
entered in it a verified
Sent a wire to Gracie
to say I would arrive
there this evening
Had lunch at the club
had to return to Hdqrs
Ordanance to get an issue
Sam Browne. Caught
the 4.pm train from Vic
Stn, which happened to be
a slow one & went via
Three Bridges arrived TunWells
6.15 pm.
Friday 4.10.18.
I Just having a real good
enjoyable time.
Saturday 5.10.18
Received a telegram this
afternoon telling me
to return to camp immed
immediately. I wired
an acknowledgement
and then caught first
train for London, arrived
there found there was
no train leaving for
Stroud until 9.15.
Spent the evening at
5A Bickenhall and managed
to get 6T.S on telephone
Found I had to report to
school of Aerial fighting
on F Tuesday morning and
that was the reason I had
been recalled. Caught 9.15
train and landed at Stroud
about midnight. Luckily found
a Leyland going to camp
so got a lift up