Fred Watson, Author at 51¶ŻÂț Science news and science articles from 51¶ŻÂț Sat, 21 Dec 1996 00:00:00 +0000 en-US hourly 1 https://wordpress.org/?v=7.0.2 242057827 Forum : Surplus to requirements… /article/1841995-forum-surplus-to-requirements/?utm_campaign=RSS|NSNS&utm_content=currents&utm_medium=RSS&utm_source=NSNS Sat, 21 Dec 1996 00:00:00 +0000 http://mg15220618.800 I NEVER thought that I’d find myself writing a lament for such a lowly
institution. But it is no longer with us, and its demise ought to be
commemorated in some way. For me, it was truly a formative influence: even
before I left school, it had shaped my future career in astronomy. It’s just a
pity it wasn’t until I recognised its importance that I noticed its
passing—twenty or thirty years after the event.

Back in the late 1950s, it was all happening: Comet Arend-Roland, the launch
of Sputnik 1, the start of Patrick Moore’s Sky at Night and the first
issue of 51¶ŻÂț. Dan Dare was in the Eagle, and
astronomy picture-cards were to be found as collectors’ items in the packets of
Brooke Bond tea. Little wonder, then, that the youth of the nation should be
drawn towards the brave new world of postwar science.

But there was something else just as potent, something that inspired youthful
dreams of exotic apparatus capable of solving all the problems of
physics—and that was the institution whose passing I now mourn. I refer to
the classic government-surplus shop. I use the term “classic” to distinguish it
from the surplus shops of today, which seem to sell mostly clothing and outdoor
equipment made especially for . . . well . . . surplus shops.

The classic surplus shop was exemplified by an establishment that flourished
down a grimy back street in the north-country town in the Britain where I grew
up. Though it hardly compared with the legendary emporia of London’s Tottenham
Court Road, it had about it an air of leading-edge technology that seems quite
absurd today.

Its owner was an erudite gentleman named Passingham. I don’t know whether his
trade made him wealthy, but he always looked comfortably off in a tweedy sort of
way. He was occasionally assisted by an exotic, boffin-like figure known as Clem
who, I think, had a day job at the local power station. As far as the customers
were concerned, Clem’s surname might as well have been Einstein.

The stock consisted entirely of surplus military equipment: aircraft
instruments, communications equipment, avionics, navigational equipment, optical
instruments—all the technical paraphernalia needed to run a world war. But
the real surprise was the rate at which it turned round. I suppose that in those
days, all kinds of technical gismos had to be home-made, and Passingham’s
provided the raw material for dozens of telescopes, short-wave radios,
photographic enlargers and audio amplifiers.

My experiences in the shop were probably typical of a whole generation of
science-minded kids—many of whom no doubt went on to become New
51¶ŻÂț readers. I used to spend hours there, fraternising with the
optics. Lured by trays of lenses and prisms, I was drawn willingly to the racks
of complete instruments—a dazzling (if rather dusty) array of “no expense
spared” optical munitions whose exact function was generally shrouded in
mystery. They ranged from humble “elbow-telescopes” with their right-angled
prisms for viewing at 90 degrees to line of sight, and the
dial-sights—little periscopes with a top prism that could rotate to view
any point on the horizon—to opto-mechanical exotica like the RAF bombsight
computer. Most were well beyond my limited means.

Astonishingly, I never gave a thought to the individuals for whom these
instruments had been designed, nor their ultimate purpose. It simply did not
occur to me that the men and women who used them would have been in constant
fear of their lives, while intent on defending freedom by threatening the lives
of others. To me, they were merely artefacts that existed for their own
sake—a naive and somewhat disquieting view.

Most of what I brought home from Passingham’s was gradually reduced to its
component parts. Like a dog with a bone, I kept going back to see what else I
could find inside. It is probably fortunate that I finally discovered the
opposite sex, and the whole government-surplus phase came to an end. While the
words “nerd” and “prat” were not in common parlance then, I had explored the
boundaries of both at a tender age.

Somewhere along the line, Passingham’s, too, disappeared—a curious
by-product of a world in conflict whose time had passed. Its legacy to me was a
comfortable relationship with optical engineering that has proved its worth ever
since—though I generally keep quiet about where it came from.

It would be impossible for me to end this lament without mentioning my
brother John. He was the original spotty little Herbert, spending his Saturdays
lurking around Passingham’s with me. But while I headed for the lenses and
prisms, he used to gravitate towards boxes of valves, resistors and capacitors.
And just as I coveted the Lancaster’s bombsight computer, he would have given an
arm and a leg for its short-wave receiver, the celebrated R-1155. Guess what he
now does for a living? Yes, he runs his own telecommunications company, and
drives around in a Mercedes.

So if, by some mind-boggling coincidence, you are reading this, Mr
Passingham, I hope you will be pleased to know that at least two of your former
customers look back on that scruffy, basement junk store with all the affection
of alumni for their alma mater. And, despite a lingering suspicion that we were
probably being ripped off, we are sorry it is no more. Rest in peace.

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Forum: A glass for all time – Fred Watson celebrates a foresighted 19th-century invention /article/1833126-forum-a-glass-for-all-time-fred-watson-celebrates-a-foresighted-19th-century-invention/?utm_campaign=RSS|NSNS&utm_content=currents&utm_medium=RSS&utm_source=NSNS Fri, 15 Jul 1994 23:00:00 +0000 http://mg14319344.800 This year, a few of us are celebrating an anniversary that falls decidedly
into the obscure category. In fact, you probably have to be a bit of a crank
to be aware of it at all. But 1994 is the centenary year of that most commonplace
of all optical instruments, the prismatic binocular.

One hundred years ago, the production shops of Carl Zeiss in the city
of Jena began turning out the German physicist Ernst Abbe’s inspired design
for a hand-held binocular that offered magnification, field of view and
robustness superior to any type then available. ‘Inspired’ because he got
it right first time. Even today, among the sleek ‘roof-prism’ models and
rubber armouring, it is possible to buy a brand-new binocular that differs
little in external appearance from the original 1894 Zeiss Feldstecher.

Abbe was not the first to think of such an instrument. Its ancestry
goes back to the 1850s, shortly after the Italian physicist Ignatio Porro
discovered that two right-angled prisms craftily juxtaposed could be used
to upturn the image in an inverting telescope. A number of manufacturers
attempted to build field glasses using this property, but found that the
desired re-erection of the image was accompanied by other, less wholesome
effects. Lacking the necessary homogeneity, the prisms of the time introduced
distortions that could not be corrected. The embryonic prismatic binocular
was dismissed as little more than a curiosity and, eventually, all but
forgotten.

Abbe, meanwhile, had joined Zeiss in 1866 and worked hard to improve
optical manufacturing techniques. In particular, he enlisted the help of
Otto Schott, a manufacturer of high-quality optical glass in Jena, in creating
‘dream’ glass-types – those with the most desirable optical properties.
By the 1880s, the stage was set for the production in Jena of a whole range
of advanced optical instruments, including the reinvented binocular.

A property of the Porro prism system is that it produces a step in the
optical axis, and Abbe used this to advantage by arranging the two halves
of his binocular so that the separation of the objectives was greater than
that of the eyepieces. The result was an enhanced stereoscopic effect,
causing the landscape to leap into striking three-dimensional relief.

This was Abbe’s masterstroke, for the 19th century’s fascination with
stereoscopic vision was absolute. Discovered by the Scottish physicist David
Brewster in the 1830s, stereoscopy was compulsive parlour entertainment
for Victorians on both sides of the Channel. At the end of the 19th century,
following the work by the German physicists Hermann Helmholtz and Carl Pulfrich,
it became a serious business, taking on strategic importance for determining
distance in the emerging technology of optical munitions.

The enhanced stereoscopic effect undoubtedly contributed greatly to
the commercial success of Abbe’s new binocular. His patent of 1893 was
actually founded on this, an earlier application for the instrument having
been refused on the grounds that prismatic binoculars were already known.
Production began the following January, and the rest, as they say, is history.
Competing manufacturers went into production with designs that avoided infringing
Abbe’s patent by various means, but the Zeiss pattern was tacitly assumed
to be the best. When the patent expired in 1908, other manufacturers quickly
copied it, producing a general uniformity in appearance that characterised
binoculars for decades afterwards.

For all Abbe’s intellectual brilliance, inventiveness and humanity
(he was pivotal in creating the Carl Zeiss Foundation in 1899), he failed
to equip his new instrument with one vital ingredient – a single, universally-accepted
name. The German language has a multitude of applicable terms, from the
archaic Prismendoppelfernrohr to the Fernglas commonly used today, with
a range of other (now mostly obsolete) names in between. The English-speaking
world fares only a little better. When the new binocular was introduced
into Britain in 1896, it was correctly described as a ‘stereoscopic binocular
field glass’. The name was too cumbersome to survive, and already, the adjective
‘binocular was being pressed into service as a noun. Unfortunately, the
intervening century has not been kind to the terminology. Common usage today
dictates that ‘binoculars’, like scissors and trousers, come in pairs. Field
glasses and opera glasses do, having originally been instruments for one
eye, but a pair of binoculars?

How is the world of optical engineering celebrating this great anniversary?
It seems that it could hardly be less excited. Zeiss is producing a commemorative
range of prismatic binoculars for the few who will be able to afford one.
And the Zeiss Historical Society of America, an international association
for people interested in such things, is planning to mark the occasion with
special presentations at its meeting in Hamburg in September. In Britain,
no particular celebration is planned. I wonder if we might be just a bit
miffed that Barr and Stroud of Glasgow – which was on the point of patenting
a prismatic binocular in 1894 – didn’t get there first.

Fred Watson is based at the Royal Greenwich Observatory, Cambridge.

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