Of Physics, Firearms, and Fireworks

Physics, Firearms, and Fireworks
(photo: Tim Jones)

I learnt only recently, while researching the early use of computers in schools, that my physics teacher from the late seventies, John Page, had died during 2009.

Better known by his nickname ‘Bumble’ (possibly after the Dickens character), he was certainly a character himself.  He was also a teacher who encouraged me to think.

Reproduced from the Gateway Magazine

For sure, Bumble covered the official syllabus: wheeling out worthy but ultimately plain vanilla physics kit like air pucks, weights, and springs.  But the most interesting discussions – the ones that have stuck with me –  followed some of his more off-the-wall demonstrations.

For example, as an introduction to Newton’s Laws of Motion and the Gas Laws, Bumble kicked off one lesson by discharging a black powder pistol at the front of the classroom.

The lesson started in the usual way, Bumble making his signature ponderous walk to the laboratory’s front desk, eyes looking at the floor.  

Entirely normal so far, except today he carried a long-barrelled  revolver in his hand, one chamber of which he proceeded to load, methodically inserting pieces of cloth, then gunpowder, then cloth again (no bullet thankfully), before compressing the package with a small ram rod.  We watched in stunned silence.

Gateway Grammar School Leicester
Gateway Grammar School, Leicester (Photo: Tim Jones)

Remember, this was all way before the Dunblane massacre or other school shootings, so I guess we felt a sense of intrigue rather than fear.  This was Bumble anyhow – he did weird stuff.   With a copper percussion cap in place, the gun was pointed in the general direction of the laboratory wall.  And fired.

Within seconds of the most enormous bang echoing through the now smoke-filled laboratory, the Head of Physics, Mr Gill, closely followed by the Head of Chemistry, Mr Scottow, tumbled into the lab looking suitably alarmed.  They’d clearly not been pre-briefed, and I still remember their expressions changing from shock to relief – and a glance of resignation between them – as the gunman stepped out of the smoke.

Stunts like Bumble’s Colt Navy revolver demo were attention grabbing and fun, but also an introduction to typically stretching discussions. 

In this case, Bumble got us thinking about how long a gun barrel would have to be before the bullet changed direction and went back the other way.  Imagine the thought processes needed for that.  First off, there’s the non-intuitive realisation that a projectile in a tube can change direction if the pressure behind it falls sufficiently relative to the pressure in front of it – which theoretically can happen in a long enough gun barrel.   Then there’s the skill of mentally extrapolating the familiar (relatively short barrel) to unfamiliar extremes (hugely long barrel).  Thinking in abstraction and at scales beyond normal experience is useful, for scientists and non-scientists alike, in appreciating the scales relevant to fields as diverse as evolutionary biology and cosmology (and presumably also super-gun design).

Sections of Big Babylon at Fort Nelson, Portsmouth
Sections of the ‘Big Babylon’ Iraqi super-gun at the Royal Armouries, Fort Nelson, Portsmouth (Photo: Tim Jones)

Then comes the actual physics and chemistry: mechanics, thermodynamics, kinetics, friction, shock-wave propagation – not to mention the mathematical tools needed (I don’t remember if we came up with an actual quantitative answer, and suspect an analytical solution is only possible with major simplification. )  The follow-on lesson might cover ballistics: catching up with the bullet after it leaves the gun.

In a similar vein, my introduction to fluid flow through constrictions and Bernoulli’s principle took the form of the largest firework rocket I’d ever seen being launched from the school playground.  In the lesson afterwards, we talked about rocket nozzle design.   It turned out Bumble was licensed to make fireworks and had designed and cast his own ceramic nozzles.  I still marvel that the thing came down ‘safely’ in the confines of the school yard.

So that’s how I remember Bumble.  We might at times have got distracted from the strict letter of the course syllabus; but that’s the nature of real-world problems if they’re studied with sufficient rigor.  And arguably as the antithesis of spoon-fed exam training, Bumble’s teaching style may not have suited all students.  But personally, I love the attitude and approach to education John Page represented, and very much hope we haven’t seen the last of the Bumbles.

Echoes of Muybridge – Photographic Pioneer

Do the four jackdaws taking off across the left-right diagonal here remind you of anything?

Jackdaws taking off
Was Muybridge inspired by their ancestors?  Click for larger image.  (Photo: Tim Jones, Darkroommatter.com)
Eadweard Muybridge
Eadweard Muybridge (Photo: WikiCommons)

For me, the regular spacing and apparent connected motion of the birds is reminiscent of  the work of nineteenth century photography pioneer, Eadweard Muybridge.

Born in 1830, Muybridge photographed many sequences of birds in flight like the one below.  But he’s probably better known for his animations of galloping horses, revealing for the first time that, at certain points, horses literally fly.

Eadweard Muybridge's Bird in Flight
Eadweard Muybridge’s Bird in Flight

Muybridge’s techniques revealed an animal’s true motion, knowledge that until his arrival had been lost in a blur of busy limbs.

Before photography, the motion of horses in motion was often mis-represented. Baronet with Sam Chifney Up, by George Stubbs.  (Photo: Tim Jones of a painting at Huntington Library)
Before photography, the motion of horses in motion was often mis-represented. Baronet with Sam Chifney Up, by George Stubbs. (Photo: Tim Jones of a painting at Huntington Library)

I should explain that Muybridge made sequenced compilations of stills taken of a single animal, while my picture is a happenstance capture of several birds taking off in close proximity and in apparent sequence: reminiscent of an airfield scramble or ducks flying up a wall.  So I’ve got an illusion evocative of Muybridge, not a simulation, and the motions of different birds cannot be linked. (Or can they? Formation take-off?  I’m reminded never to under-estimate the Corvidae family!)

By another happenstance, it turns out Muybridge was born and raised in the town where I now live: Kingston-upon-Thames in Surrey.  And while he spent most of his working life in America, Muybridge left the materials of his important photographic legacy to his home town, where they reside in the Kingston Museum and Archive, five minutes walk from where I’m sitting.

A good selection of Muybridge material is normally on display in the museum, representative of his animal and human figure work, but also featuring his definitive 1878 panorama of San Francisco (link to America Hurrah website).

Muybridge’s San Francisco Panorama (Photo credit: America Hurrah)

And if you’d like to find out more about Muybridge and his legacy, there couldn’t be a better time.  Beginning this week, Wednesday 8th September, the Tate Britain will launch a Muybridge retrospective, and our own Kingston Museum will, from September 18th, host the Muybridge Revolutions exhibition, featuring unseen exhibits like Muybridge’s collection of Zoöpraxiscope discs.  The Kingston exhibition is part of a broader range of Muybridge related activities being coordinated by Kingston University with Kingston Council.

Fallow deer.  (Photo:Tim Jones, Darkroommatter.com)

But returning to my jackdaws in a more romantic frame.  I like to ponder Muybridge walking the same routes I take  today as I photograph the wildlife of Home Park; his meeting the ancestors of present-day jackdaws, deer and rabbits; and with his frustration at the unfathomable rapidity of their movements, the seed of motion photography being sown….

Update 12 October 2010

The powers that be are projecting Muybridge animations onto the side of Kingston on Thames police station. Very nice.

Muybridge on Kingston upon Thames police station
Muybridge on Kingston upon Thames police station (Photo:Tim Jones)
Muybridge on Kingston upon Thames police station
Muybridge on Kingston upon Thames police station (Photo: Tim Jones)
Muybridge on Kingston upon Thames police station
Muybridge on Kingston upon Thames police station (Photo: Tim Jones)

World War II Road Block – An Eerie Reminder of Darker Times

Here’s some not so sophisticated, but still deadly serious, military technology we discovered while walking along the river bank this morning.

Anti-tank Road Block
Anti-tank road block near Sunbury

Thankfully it never happened, but in 1940 there was every expectation that Britain would be invaded by Germany.  One preparation for that was the building of a series of defensive lines around London and other areas of the country.

Anti-tank roadblock concrete cubes near Sunbury
Blocks extend to the water's edge

The example here is a road block designed to slow down tanks and other armoured vehicles as they progressed in expected Blitzkrieg fashion across the green and pleasant land.  The concrete cubes extend down to the water’s edge, leaving a small gap that could be plugged with a removable barrier, possibly a duplicate of the piece of bent railway track, or hairpin, still in place.

Bent railway track or 'hairpin' anti-tank barricade
Bent railway track or 'hairpin' barricade

I did a bit of fishing around, and discovered this particular defensive position close to Sunbury-on-Thames was part of the Outer London Stop Line.  Other types of defense included concrete pillboxes, minefields and trenches, plus use of natural features like the river here.

A road block like this one would likely be defended by another firing position nearby, so it wasn’t just a case of the enemy turning up and spending five minutes pulling out the barriers.

There are many similar features around UK, but I don’t think the seriousness of the threat at the time, or the extent of the defenses put in place to counter it, are widely known.

It’s also sobering to think these blocks were put down only 22 years before I was born.

More on British anti-invasion preparations of Word War II here.




Latest Reading – Dr Tatiana’s Sex Advice to All Creation

O.K. – so I was the last person on the planet to see E.T., I still watch TV on a cathode ray tube, and I’m seven years late reading Olivia Judson’s hugely entertaining, accessible, not to say stimulating, guide to evolutionary biology: Dr.Tatiana’s Sex Advice to All Creation, making this an admittedly after-the-event review, but a recommendation all the same.

Throughout the guide, Judson stays in character as sex therapist Dr Tatiana, helping all manner of creatures out with their sex problems – agony aunt style.

Olivia Judson
Olivia Judson (Photo: Tim Jones)

And creatures it is.  Ranging from a stick insect jaded with the tedium of ten week copulations; to a praying mantis who finds sex so much more satisfying after biting off her lover’s head; to a fruit fly dismayed that he’s run out of sperm; to a queen bee’s concern that her mates leave their genitalia inside her after sex.

Mixed in with these familiar heterosexual and homosexual practices are gang rape, cannibalism, self-sacrifice, and deception – all to a background of hopeless promiscuity.

The entertainment is delivered by a fascinating cast of cads, bints, sluts, and whores, bonking away at romantic locations  – including the inside of a rat’s intestines.

Lestes sponsa (Emerald Damselfly)
Damsel flies “have evolved some of the fanciest penises around”  Lestes sponsa (Photo: Tim Jones)

That’s the language and tone then: spirited rather than crude I’d say, but probably not first choice for your great gran.

The anthropomorphism is extreme, caricatured, and humorous enough to make any questions around ambiguity and appropriateness non-issues (at least for me).   It’s clever too, each section introducing a discussion on an aspect of evolutionary biology with some fun, if not a giggle, then quickly morphing into serious, yet always palatable, science.

Stick Insect
Stick insects can copulate for 10 weeks continuously (Photo: Tim Jones)

The concepts are familiar: sex ratios, altruism, asexual vs sexual reproduction, dangers of recessive genes and such like; so perhaps I’ve not been under a log after all.  I kept getting flashbacks to ideas I’d first read about in Richard Dawkins’s Selfish Gene or Matt Ridley’s The Red Queen.  By comparison, Judson’s style in the guise of Dr Tatiana is deliberately and overtly entertaining; but not at the cost of scholarly rigor (there are 62 pages of  Notes and Bibliography).

Praying Mantis
Male praying mantis prefer not to give head (Photo: Tim Jones)

Previous reading certainly didn’t stop me picking up a bunch of new facts and figures on the more macabre and icky side of sexual reproduction.  Knowledge any schoolboy/girl  would be proud to have in his/her  armoury.

Insects dominate Dr Tatiana’s surgery hours, but mammals and birds  do get a look in.   Like the girl hyena concerned over the size of her pseudo-phallus, or the moorhen bemused that his girlfriends are always fighting with each other.

But now I’m giving too much away.

Amazon have the paperback Dr Tatiana on for about £6.50 in the UK, and there’s also a DVD of the TV series based on the book.  No brainer – go get it!

A Brush with Base Jumping

Base jumper in the Lauterbrunnen Valley, Switzerland (Photo: Tim Jones)

I see from the TV listings that Channel 4 (UK) will tomorrow be airing  The Men Who Jump off Buildings: a documentary about the extreme sport of base jumping.  Launching from Buildings, Antennas, Spans, Earth (hence BASE), base jumping practitioners have only seconds to control their descent  and deploy a parachute.   Jumps from buildings and cliffs are particularly demanding due to the danger of hitting something sideways on the way down.

Base jumper in Lauterbrunnen Valley (Photo:Tim Jones)
Base jumper in Lauterbrunnen Valley (Photo:Tim Jones,Darkroommatter.com)

While the Channel 4 show promises to focus more on jumps from buildings, it reminds me of a base jump from a cliff side I witnessed in 2007, in Switzerland’s Lauterbrunnen Valley.  The rapid-fire sequence of photos I took at the time should convince you that stamp collecting isn’t such a bad hobby after all.

I later discovered Lauterbrunnen is something of a base jumping hot-spot, famous for the quality of the jumps, but also for the number of related deaths in recent years.

The sequence of 16 pictures in the gallery below shows the various stages of the jump, including the free-fall glide and chute deployment; the main chute is activated by a smaller chute the jumper holds and throws out at the critical moment.

Although the guy in the pictures landed safe and sound – I had a chat with him later – the sequence  shows him fighting to unravel a tangled harness.  Jumpers say every jump is different, so an ability to think quickly on the spot is as important as understanding the theory.

Lauterbrunnen valley (photo:Tim Jones)
Lauterbrunnen Valley (photo:Tim Jones, Darkroommatter.com)

The timing and manner of the chute’s release depends on many factors, including the jumper’s velocity, which in some cases may be below the terminal velocity of around 120 mph.  It goes without saying that the time available to avoid objects and adjust parachutes is severely limited.

Apart from one holiday paragliding experience in the Med., I’ve only worn a parachute while flying gliders – and thankfully never had to use it.  And for now, exhilarating as I’m sure base jumping is, I think I’ll stick to walking up mountains rather than jumping off them.

Accidental Pepper’s Ghost

This picture of a rare bakelite coffin in the London Science Museum’s plasticity exhibition is also an accidental recreation of the Victorian optical illusion known as Pepper’s Ghost.

Pepper's Ghost effect in a bakelite coffin at science museum
Bakelite coffin at the Plasticity exhibition, London Science Museum (Photo:Tim Jones)

In one version of the illusion, an audience member stands in the coffin on a stage, and the rest of the audience watch as he gradually decays into a dancing skeleton before their eyes.  In that case, the image of a brightly lit skeleton placed in a pit in front of the stage is reflected by an angled sheet of glass placed between the audience and coffin.

On similar lines, a less elaborate experiment you can try yourself with a sheet of plane glass and two tea-lights is described in this piece from the Naked Scientists.

I’ve had this picture for a while, and only noticed the Pepper’s Ghost effect when I pushed the shadow enhance slider on iPhoto.  Quite scary seeing oneself encoffined.  Good job I’m not superstitious….

Out of the Archives – Calculators, Computers….and Stuff

sinclair scientific calculator
Sinclair Scientific Calculator (Photo:Tim Jones)

This picture of a Sinclair Scientific is the latest recovered image from the 30 year  archive of negatives I’m dutifully working through.

The reflections in this post are also prompted by this recent post on Andrew Maynard’s blog, (2020science), describing the sophisticated graphing calculator his children are required to have for school.

A pass-me-down from my brother, the Sinclair Scientific was my first electronic calculator.   Built from a kit in 1975, I used it to prep for the UK O-Levels when I was 14 or 15; in the O-Level exams themselves we only had log tables :-P.  By the A-Levels (16-18), I’d upgraded to a Casio fx-39.

John Napier, father of logarithms (Image: Wikicommons)

As it turns out, the calculator my nephews require for today’s GCSE syllabus is a Casio; but  costing around £5, against the £75 or so for Andrew’s Texas Instruments machine.

An interesting feature of the Sinclair Scientific was its use of Reverse Polish Notation (RPN): an unusual but logical way to express calculations. Under RPN, the operator (+,- x, / etc) comes after the operands (the numbers); so the more well known Infix representation of 7+8 , in RPN becomes 7 8 +.  RPN is more memory efficient for computers – a bigger deal once than it is now.  Today, modern computers just translate into RPN without us seeing it.

You might think getting to grips with RPN was an awkward distraction for a 15 year old, but it proved handy background when it came to writing programs for this:

Stantec Zebra
Stantec Zebra (Photo from the Stantec Zebra manual)

I guess this was our graphing calculator.  Not exactly pocket size.

If memory serves, my school, named the ‘The Gateway’, acquired the 1958 Stantec Zebra from the local university; before that it was with the Post Office.

punch card
Punch card

A small team of students operated and maintained the machine which, filled with hot valves, would frequently catch fire and give the occasional electric shock.   This could never happen today of course, on safety grounds alone.  But at the time, the teachers and students took it all in their stride, seizing the opportunity to build a short extra-curricular programming course into the timetable.

Programming lessons involved: writing code on cards with pencil and paper, encryption onto punched cards that the Stantec Zebra could read optically, then receiving line-printer output of the results.  Looking back, it’s amazing any of this happened – a great opportunistic use of a rare resource.

Powertran Comp 80 (Photo:Tim Jones)

Pupils who later built their own computers, like the Science of Cambridge MK14, a basic kit machine launched in 1977 with about 2k of memory, or the Sinclair ZX-80, were doubtless inspired by the presence on site of their valve-driven (but still significantly more powerful) ancestor.

An interest in computers in this era meant just that: an interest in the information structure, solution algorithms, programming and hardware.  High level programming languages, like BASIC even, were too memory inefficient to exist, and ‘games’ typically comprised simple models around the laws of motion; moon lander simulations were popular.

Our household variously hosted a home-built Powertran Comp 80, a Sharp MZ-80A (including some early green dot graphical capability), a Sinclair Spectrum and Sinclair QL.  I’ve put pics of these and various other devices I’ve owned in the gallery at the end of the post – minus the obvious PCs that started with a Viglen P90 in 1995.  Also our Creed 75 teleprinter – the only one I’ve seen outside the London Science Museum, this true electro-mechanical wonder was brought to good working order save for the chassis occasionally running live with mains voltage.

Creed 75
The Science Museum’s Creed 75

Are there any world-changing messages to be drawn from all this nostalgia?  Possibly not.  But I’m reminded how very hands on we were in just about everything.   And that’s relevant given the buzz today about how kids might not be getting enough practical science and engineering experience in schools (I’m thinking of comments most recently made by Martin Rees in the Reith Lectures).

No one is arguing kids need a nuts and bolts knowledge of all modern gadgetry, but I do think off-syllabus projects like the Stantec Zebra (but perhaps less dangerous) are a good thing in schools.  They show how diverse academic subjects come together in an application, making the theory real.  This is pretty much my mantra in this earlier post about the Young Scientists of the Year competition.   I would have thought such projects give a school a sense of identity and foster a bit of team spirit?

But it’s really an area I’m out of touch with.  Does this type of stuff happen in lunchtime science clubs?  Is there time in the curriculum?  Do teachers have the time and/or skills?  Or has our health & safety culture, however worthy, killed off anything interesting?

 

Also of interest

Kids Today Need a License to Tinker (Guardian 28/8/2011)

Blinking Crows

Question to any crow experts out there.  I recently spotted these two standing together, and noticed that they seemed never to blink at the same time – as if consciously taking it in turns.   It’s easy to tell when a crow blinks by the opaque whiteness of the inner eyelid.  This went on for a minute or two.

crow
Nudge, nudge...
crow
Wink, wink...

crow
Say no more...

So, is this some kind of coordinated look-out tactic crows and/or other birds follow to maximise safety?   They were long leisurely blinks, so that might make sense.  Or was this a one off behaviour –  and I’m making up my own stories?

The things that preoccupy one on these warm summer evenings…..

Update September 2010

I found this pic going through my archives; taken in Windsor, UK.  Look at the eyes.   Still a small sample of two.

Blinking crows in Windsor
Blinking crows in Windsor

Recipes, Formulas And Processes

Readers interested in early twentieth century chemistry, processes, and tricks of the trade used by industry and in the home, might like to check out the online edition of Henley’s Twentieth Century book of Recipes, Formulas and Processes, Edited by Gardner D.Hiscox – a pdf of Cornell University’s 1909 copy at the Internet Archive.

hiscox recipes formulas and processes by G.D. Hiscox
Recipes Formulas and Processes by G.D. Hiscox (1907 edition)

I’m lucky enough to own a 1907 first edition of Hiscox’s classic work, and love the way my copy is dis-colored and bleached by chemical splashes.  Not by me, I hasten to add.  But this book has for sure been used for its intended purpose!  Whether the former owner, a James McQueen Jr. according to the bookplate, lived long and prospered because of its secrets, or in spite of them, is a different matter.

Secrets intended for all; the preface:

In compiling this book of formulas, recipes and processes, the Editor has endeavoured to meet primarily the practical requirements of the mechanic, the manufacturer, the artisan, and the housewife.

Some of the information is innocuous enough.  You can learn how your great grandmother made blackberry jam.  And Celery Clam Punch or Cherry Phosphate (with real phosphoric acid, maybe the origin of cherry coke?) sound refreshing for a summer evening.

But some of the medical cures are distinctly dodgy.  We worry enough today about tanning products, but Hiscox’s cure for a tan, made from bichloride of mercury, sounds lethal.  Helpfully, he shares with us that:

This is not strong enough to blister and skin the face in average cases.

Phew, good job most folk are average.  Responsibly, he adds:

Do not forget that this last ingredient [the mercury compound] is a powerful poison and should be kept out of the reach of children and ignorant persons.

Folk would have taken Hiscox’s Cannabis indica based cure for corns in their stride (ouch!).  And concern over the pinch of cinnabar in his nail polish would be just another case of health and safety gone mad.

But surely, even by the standards of the time, Hiscox’s idea of a light-hearted party trick must have raised some eyebrows (or literally blown them off): like ‘To take boiling lead in the mouth’, ‘Biting off red hot iron’, ‘Sparks from the finger tips’.  And ‘The burning banana’ doesn’t bear thinking about.

hiscox recipes formulas and processes
Recipes, Formulas and Processes (1907 edition)

Some recipes were probably safe, but just sound a little icky.  Like a nice pomade for sir’s hair, made from vaseline oil and beef marrow.   Blue hosiery dye called for some ingredients I’ve never heard of: like 4 pounds of Guatamala and 3 pounds of Beugal Indigo; and others I have heard of: like 1 pail of urine.  Hiscox also contains lots of paint and ink recipes but, disappointingly, there’s no mention of the infamous Mummy Brown.

‘Solid Alcohol’ sounds quite useful, maybe as a firelighter.  I made something similar as a schoolboy, by dissolving soap in methylated spirit.

There’s nothing in Hiscox to separate the domestic from the industrial.  Content is alphabetically indexed, but otherwise all mixed up.   The section on glass includes industrial formulas for making different glass types and colourings in the furnace, but also includes instructions for a home-made glass grinding device.

Interestingly, Recipes, Formulas And Processes was republished through many revisions and editions into at least the 1930s.  But I’m sure today there is nothing quite like it – unless we include the internet as a whole.

On another tack, it’s worth remembering that when Hiscox was published, the welfare and commercial infrastructure we take for granted today (some of us) was much less developed or non-existent.  No popping down to the mall for a ready-made solution to every task.   Folk just did more of their own stuff.

And should you decide to do more of your own stuff, don’t do it from Hiscox!   He’s academically interesting to browse, but clearly some of his recipes and ideas are best left well alone.

Out Of The Archives – Telescope Tales

I’ve been amusing myself this evening scanning old black & white negatives and colour slides into the computer: strips of film that have languished in negative files on top of cupboards for years.  It’s a boring process, but punctuated with the reward of finding something I thought was lost, or a negative that was never printed.

developing tank developer fixer darkroom
Home developing. This is how we did it….
developing trays darkroom
when I were a  lad…..

Some of the pictures go back to 1973, and are an unwelcome reminder of my antediluvian origins.  But they’re also revealing of the state of technology at the time, and what I was doing with it.  All the black and white pictures in this post are from the archive.

zenith enlarger
This is not a telescope

The photographic process itself is a prime example: the relative time  and cost of developing and printing my own films being one reason many pictures haven’t been properly seen until now.

Things sure have moved on.  I asked my 15 year old nephew if he’d ever used film, and after clarifying I didn’t mean video tape, he confirmed he’d never touched the stuff.  Silly of me to ask really.

Regrettably, some of the more fun, not to say embarrassing, pictures from the archive are not suitable for public display.  But I’m happy to inflict the sci-tech oriented discoveries – starting today with these pics of my first serious astronomical telescope.

fullerscopes six inch reflecting telescope
Same paint job as the 200″ on Mount Palomar

The main components were bought in 1977, and this photo of the telescope in its observatory is probably from 1979.  The instrument is a classic Newtonian reflector of a design that hasn’t changed in hundreds of years.  It has a 6″ primary mirror, and was built by Fullerscopes of London, the same company that made Patrick Moore’s fork-mounted 15″.  The mount is a Fullerscopes Mk III German Type equatorial.  The ancillaries: motor drives, plinth, finder, camera attachments, and the observatory itself are home built.

fullerscopes six inch reflecting telescope

To be accurate, this was my second telescope, the first being an entirely home-built open-tube reflector in an altazimuth type cradle.  Constructed almost entirely from sturdy aluminium bar stock – largely because that’s what I had – it all proved a little unwieldy.  No photos survive – probably for the best.

Reflecting telescope made by Isaac Newton (Photo:Tim Jones, taken at the Royal Society)
Made by Newton (Photo:Tim Jones, taken at Royal Society)

The 6″ was mainly used for visual observations.  I later added an improved synchronous motor drive to the Right Ascension (RA) axis to make the instrument more suited to astrophotography, but as that happened in 1980, just before I left home for university and ever on, that feature was little used.

Warning – Telescope building aficionados, engineers, (and all other interested readers….!) only

Assembling, augmenting,  or building a telescope from scratch is an excellent engineering, as well as scientific, training.  To save money, I purchased only the RA axis worm drive from Fullerscopes, with a view to reverse engineering it and building a copy for the declination axis. Operations to do that included aluminium casting, worm screw cutting, and making my own integrated roller ball-bearings on the worm shaft (to remove any trace of play, and hence instrument movement).   Thankfully, my brother was building a model steam engine at the time, so a good selection of machine tools were available around the home.

Myford ML7 lathe. Every home should have one (here operated by my brother).

I realise now that some of these operations were quite sophisticated engineering tasks, particularly for a 15 year old – probably why things didn’t always turn out as planned.  I struggled to reproduce the 4.5″ phosphor bronze worm wheel (although the trick for cutting a worm wheel, by winding a tool-post mounted wheel into a spinning tap mounted between lathe centres, I find fascinating and elegant), and instead adapted an ex-military gun-sight for the declination axis.  That said, the worm unit I’d made was better than the original, and eventually replaced it.

screw-cut worm in ball-races / cradle
Great British engineering….

The RA motor connected to the drive worm via a gearbox, also homemade using mecano gears mounted in a solid block of steel, the centre of which had been milled out on the lathe and fitted with individually turned and reamed phosphor-bronze bushes.  The whole drive assembly was bolted to the plinth and linked to the final worm gear on a universal joint.  This all worked fine, unless the telescope was incorrectly counter-balanced, when teeth would expensively shear off the little mecano gear wheels.

Moon

Despite these set-backs, or perhaps because of them, it’s my firm belief that this activity set me up well to tackle life’s later challenges: like building my own research equipment and mending the car.

The telescope’s plinth and observatory have their own stories.  I’d read somewhere that telescopes need a rock-solid mount, and that plinths mounted in concrete are superior to tripods.  In the photo, you can just see the top of a 5ft x 5″ x 1/4″ steel tube, 2 ft of which is buried in a 3ft square cube of concrete.  The base of the observatory is covered in paving stones laid on sand, with a gap around the central concrete block to prevent footstep vibrations reaching the plinth.  The plinth was capped by a 7″ square x 3/8″ thick oxy-acetylene welded plate.  I remember this well, as the welder had to commission an unusually large nozzle for the job.  This was of course total overkill for a 6″ reflector; but I suspect I harbored secret fantasies of some day owning a more substantial instrument.

Lyra

The observatory was made from resin bonded plywood on a pine frame.  Originally designed as a run-off shed, I switched to the fold-off roof idea when the weight of the structure dictated a need for major railroad-type work adjacent to the observing area – effectively doubling the project’s footprint.  In practice, a south-facing aspect and relatively low observatory walls meant the compromise solution made little impact on sky visibility.  A telescope mounted permanently out of doors is always ready for action – an important consideration with UK weather –  with no need to wait for thermal stabilisation of the optics or to spend time aligning the equatorial mount.   It goes without saying that, like all the world’s great observatories, it was painted white.

I keep saying ‘was’, because Mount Tim was decommissioned in the early nineties, such that you’d never know the paved area had ever  been anything other than a regular garden patio.  Amusingly, the plinth proved immovable, save for the use of explosives, so was instead ceremoniously tipped on its side in a shallow grave.  I sometimes wonder what a future Tony Robinson might make of it.

Coming back to Fullerscopes.  Buying a telescope in 1976 was not like popping down the road to Curry’s and carrying it home under your arm.   When my father and I first visited Telescope House on the Farringdon Road, we were greeted by Dudley Fuller in person.  He’d formed the company a few years earlier by buying out the historic but failing maker of optical instruments – Broadhurst & Clarkson Ltd.

We talked about my telescope-making efforts to date, and what I needed from Fullerscopes.   He was wary of my plans to attach one of his diagonal mirrors to my homemade spider using glue (EvoStick No.2 – if I must!), but we agreed a package – including a Fullerscopes spider – and placed the order.  (The spider sits in the top of the telescope tube and holds a diagonally placed mirror that diverts light into the eye-piece.)  A month later, I returned to man-handle this tribute to Sir Isaac through the streets of London and back to Leicester  – by train.

What I’m using today: Meade ETX-90.

Telescope building was still being done in a traditional way.  Fuller explained that all the brass tube-work on his telescopes was hand made using Broadhurst & Clarkson’s original equipment.  That meant the brass sheet was rolled on an antique mill by hand, then soldered along the seam.  On my telescope, the solder seam is visible on the brass focusing mount and Barlow lens adapter tube.  The economics of this, particularly on parts destined for smaller instruments like my 6″, and at a time when Japan was starting to export mass-produced alternatives, must have been unsupportable.  I’m guessing that’s the reason the Farringdon road shop closed down in 2005 and Telescope House moved out of town.  It looks like they’re still trading though, with Patrick Moore’s endorsement into the bargain. (Telescope House website).  But they don’t seem to be making their own instruments any more – please correct me if you know different.

Meade ETX90
Meade ETX90

There’s a related and slightly surreal twist to the story here, concerning my move to London in 2000.  Needing a more portable telescope for out of city viewing, I visited Fullerscopes, now the UK agent for Meade Instruments Corp. of the USA, makers of the compact Cassegrain-Maksutov telescope I was after.  The odd thing was, when I got chatting to the guy who handed over the box, it turned out he had personally been involved in making the brass-work for my 6 inch reflector 24 years earlier!  It’s a nice story.

Anyhow, I hope that wasn’t completely boring and self-absorbed.   If nothing else, it may have given you an insight into what I was getting up to in my formative years.  You know, when I should have been out doing drugs, smashing up cars, and getting my underage girlfriend pregnant – like a normal teenager 🙂

Don’t forget to check back for the next exciting edition of Out Of The Archives……