Charm Offensive: A Spyglass Comes This Way!

A telescope that fits in the palm of your hand.

A telescope that fits in the palm of your hand.

 

 

 

 

 

 

 

 

 

 

 

 

 

Whichever way you slice it, the invention of the telescope revolutionised human civilization and extended our reach far into the wider Universe. And though the telescopes of the 17th century were very crude and unwieldy by today’s standards, the arrival of the achromatic doublet greatly increased their convenience and ease of use. The new technology, patented first by John Dollond in 1758, was quickly exploited to produce portable instruments for the military and the navy in the form of the nautical or ‘signalling’ telescope. And while Dollond & Co. made a fortune selling these telescopes to customers all over the British Empire and beyond, it was not long before an army of other opticians took their cut of the market, by fashioning their own renditions of the instrument.

An un-coated object glass of one inch aperture.

An un-coated object glass of one inch aperture.

 

 

 

 

 

 

 

 

 

 

 

 

 

As a result, although many authentic signalling telescopes built by the finest opticians in Europe and the New World can still be had for prices that reflect their provenance in the 21st century, many other antique models fashioned by more obscure artisans can be purchased relatively cheaply even in today’s market.

I’m no antique collector though, but I was pleasantly surprised to see that the classical spyglass, the signalling telescopes of old, are still being made today. I took delivery of one such instrument this very afternoon. Tipping the scales at about 380 grams, the telescope collapses to just half a foot (15 cm), making it fit snugly in your pocket, and extends to 15 inches – in three draws – when pressed into service.

An ornate eye lens.

An ornate eye lens.

 

 

 

 

It was only in the aftermath of World War II that anti-reflection technology in the form of a thin layer of magnesium fluoride was first applied to lenses to increase light throughput and decrease glare, but the ship telescopes that accompanied the soldiers and sailors of the 18th and 19th century were entirely un-coated.

In this capacity, though some of my contemporaries might baulk at the thought, I was actually delighted to see that the lenses in my ‘Ship Telescope’ were also un-coated and thus more consistent with those from antiquity. The instrument  has an objective of one inch (26mm) aperture and delivers a correctly orientated image with a power of 6 diameters. Objects can be focused from infinity to just a few feet away! Focusing is intuitive, achieved by slowly sliding the draw-tube in and out, as appropriate.Optically, the instrument isn’t great – compared to all the wonderful and inexpensive mass produced telescopes we enjoy now – but I believe it is more or less typical of what these instruments could deliver in their day. Specifically, it displays strong field curvature, some obvious lateral colour, minor internal reflections when turned on very bight objects, as well as moderate spherical aberration in a very narrow field of view. But to dismiss the instrument as optically shoddy is to completely miss the point! The centre of the field is good and sharp and perfectly adequate to the task intended for it. And what it lacks optically, it more than makes up for in other ways.

The three-draw spy glass extends to about 15 inches.

The three-draw spy glass extends to about 15 inches.

Although my model only set me back about £35 (inclusive of delivery), I was pleasantly surprised by the build quality of the instrument. The main tube has a stitched leather sheath and the three draw tube is entirely fashioned of polished brass. Each draw glides smoothly over the other with just the right amount of traction. Handling the instrument for any length of time imparts the strong aroma of cuprum et pellis in the palm of one’s hand that is so reminiscent of bona fide antique pieces. It also came with a nicely machined brass dust cap for the objective, though without a soft case or box to store it in.

I spent the odd idle moment enjoying the landscape around my home with the instrument and once my boys arrived back from school, they were eager to try out the new pirate ‘scope for themselves. All in all it was a big hit with the entire family and just a joy to use on a bright Spring day. A telescope like this would make a thoughtful and relatively inexpensive gift for someone who would like to see the world through the eyes of a child once again. It will bring you all the way back to the time of your youth, when the world seemed more innocent than it is today; an ornate and charming memento of a by gone age.

Oscar keeps a close eye on those roosting corbies.

Oscar keeps a close eye on those roosting corbies.

 

 

 

 

 

 

 

 

 

 

 

 

 

De Fideli

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