24 
TECHNICAL EXHIBITION 
Of course, we had the advantage that we had the first panchromatic plate, and that was 
a tremendous advantage. That had just been invented by the great Dr Mees who, I 
regret to say, died only a fortnight ago; he was one of the greatest photographic chemists 
in the world. I would not like you to think that we did not produce stereo photographs 
from the air in those days because we did, and we not only made the visual ones but I 
remember projecting photographs for the benefit of the staff of the Second Army in 
the approved way of dyeing red and green and looking through reverse spectacles. 
I always remember a disappointment in respect to that because 1 was particularly 
anxious to impress General Trenchard, as he was then, in the marvels we had accom- 
plised, but, would you believe it, he really could only see out of one eye and could not 
get any relief out of it at all. 
It was obvious, of course, as time went on that with better cameras, better 
mountings and better aeroplanes the future was going to be rosy. When you know 
your focal length and you know your separation, you can go a long way and my good 
ness you have done it. I do want to congratulate and thank those noble firms from 
abroad which have transported those remarkable instruments which I saw here this 
morning. I hope they will be rewarded by orders for their initiative and kindness in 
bringing over the remarkable exhibits which we have seen. 
As an ordinary private motorist I have a slight grouse against map-making in 
this country. First of all, let me say that I consider the products of the Ordnance Survey 
to be the finest maps in the world but — that is a nice word — the point is that roads 
and roundabouts get created very quickly in a few months. I know that there are many 
parts of England where you just cannot get a map of the area from which you can find 
your way about. The Ordnance map is a precision map. What 1 want to impress upon 
map-makers is that as a motorist I do not mind if a gate-post to a farm is six foot in the 
wrong place; it does not worry me at all! All I want to know is where the new roads are, 
where the new roundabouts are, and so on. Mapping is not a state monopoly; we are 
still in a way a free country. I do sincerely hope that some enterprising firm will produce 
new maps - rough ones, if you like - every six months in order that I may find my way 
about. 
What developments lie before you? I see, of course, that most of your efforts are 
on maps, and very rightly so because I understand that only thirty per cent of the world 
is mapped, which is very extraordinary. However, the uses of this science are manifold: 
forestry is using it; civil engineering has found that it saves immense labour; there is 
the great interest in archaeology; stereoscopic photography in surgery is almost a 
necessity today; I understand that criminology is helped thereby; and even tailoring uses 
it. I think that last use is a splendid idea. You could just go in, be photographed and 
find a suit which will fit you. 
However, there is no end to the scope before you. I should like to say what an 
interesting life must lie before many of you in this because there are so many subjects 
which this form of photography lends itself to. 
In conclusion, I want to thank very much the Governing Body of this great 
University of London for allowing us to use this great hall and putting it at our disposal 
for the delivering of those papers and lectures to which some of us - not all of us - 
are looking forward to listening. However, it is an exchange of views of technicians, and 
as Mark Twain once said about Coney Island: “If you like that sort of thing, that’s the 
sort of thing you like.”! I will leave it at that. We have had great help and courtesy from 
the University. Again, l should like to thank the exhibitors. I thank Mr Wills and his 
Committee and all those who have rallied round this exhibition which I hope will be a 
great success. 
I have pleasure in declaring it open.