A Dollond 8-sided telescope, from 1760

This Dollond telescope is of a type of design that I honestly thought I would never be able to own, or afford if the opportunity arose. I believe that it is said that the 8-sided design was introduced to create flat sides, so that the telescope would not roll around on a ship, and fall on the floor etc.

8 sided 1bThis was in the late 1700s, when ships were made from wood, and every ship had at least one crew member who was a carpenter, and plenty more crew who were accustomed to sorting out and fixing wooden planks! So it defies belief that any ship’s deck would not have been equipped with wooden retaining slots, hooks or pegs that allowed a telescope to be secured, not just from rolling but also from being thrown into the air!

This is not to say the flat sides of an 8-sided telescope do not provide a more secure surface to place the scope safely on a table: this is useful. But the main body, or the barrel of the telescope is not what normally touches a large flat surface, the metal rings at either end are larger in diameter than the flat faces, so it is on these round rigs that the scope sits, when you put it down on a table. So it still rolls! To put it down safely on end has to be hanging off the edge of the table – which introduces the hazard of being knocked off by passers-by.

Some of the collection in August 95.

Some of the collection in August 95. The paving slabs are 2 feet wide.The sunshade on the 8-sided Dollond can be seen to have lost a lot of the silver plating: as have the rings at either end of the main barrel. Below is a brass bodied Cousens of Swansea scope and a Dolland scope from Walney Island, of which more later.

Why 8-sided?

The reason Peter Dollond built this style of telescope for his naval captain customers I think is the same reason that this is the one I have preferred to use every time I want to identify a passing aeroplane, for the last 20 years. It gives a good magnification, with a relatively wide angle of view (for a telescope). But, as it is nearly 4 feet long to achieve this magnification, many alternate designs built at that time would have had to use a relatively more solid wooden barrel, and this becomes heavy to use. Probably with an eye at one end, you are not comfortable if required to support a heavy weight from a pivot point (hand hold) about 2 feet down the tube, unless you have an extra long left arm.

This telescope is constructed from what might be described as flattened C-sections of mahogany, making up the barrel, in the same way as a split cane fishing rod was designed as the lightest rod that could provide strength, for fly-fishing. So the result is a very light weight and easy to handle tube, which can support the heavy weight of the objective lenses and sun shade mounted on the end, without warping. This makes it very easy to use (for me) pointing up in the air looking for aeroplanes, where you rarely have a support pole to work alongside. But on a ship, you might be on a rocking deck, with the support structures attached to the hull being buffeted by waves: much better to have a scope you can hold freely and without effort, to counter the wave action. Significantly, no telescopes after this date really solved this problem, except for the tapered wooden barrelled versions made in the early 1800s.

Why are they so rare?

Actually, 8-sided scopes are not rare: there are models sold regularly. But these tend to be 12-24 inches long, and are made from a solid wooden tube, planed into eight flat sides: why I am not sure, maybe it was the fashion. There are very few 8-sided scopes around made from eight separate bits of wood. This is probably because they are subject to damage, the wooden pieces split apart or break when dropped. They are not strong enough to hold the objective lens construction really, and this pulls off.

This has happened to me, with this telescope: an accident broke off the objective. What would a ship’s captain do? He would give it to the carpenter. Actually, its an easy job to shorten the tube by 1cm, file it down to be round to take the ring that holds the objective, make some new screw holes, and its complete. And the focus – well the eyepiece tube just has to be pulled out by an extra 1cm, it’s a built in next generation feature.

A slight design criticism, or frailty, is that the objective lens screwed on to the far end is very vulnerable to being knocked against things, and when the telescope is 4 feet long I guess the end can fall off overboard! So maybe that explains why there are few complete units around: bits of them fell off ships. Another problem is that they are very long: for many years this one lived on two brass hooks above the dining room door, so that I could grab it on my way to the back door to go outside and catch a passing aeroplane. The inevitable accident was that it fell off the hooks one day. Now it is fitted with two cable ties, which have secondary ties in a loop over two different hooks in the ceiling rafters just inside the patio door: a new exit for me to catch the passing aeroplanes. It is also well away from passing children and Hoovers.

This telescope

8 sided 1aThis unit, apart from the wooden barrel, was designed and produced as a single draw made from brass, plated with silver. The fittings on the end are both of copper and brass, typically the rings I think are copper, and were also silver plated, when the scope was built. When I bought it in 1995, the sunshade was badly bashed about, and with not much silver plate left. Similarly both of the connection rings to the wooden section were lacking silver plate, as was the eyepiece finger hold, which presumably from the wear of fingers over the years, was reduced to brass.

The mixed brass and copper connection rings, with the plating worn away.

The mixed brass and copper connection rings, with the plating worn away.

The option available to me was to recover the most damaged/unplated parts by bright nickel plating, which I organised. The silver plated draw tube and the very end of the scope at the eyepiece were left as originally silver plated. The draw tube shows some wearing away of the plating at the finger pressure points: the end plate on the eyepiece bears the stamped name of “DOLLOND”, with “LONDON” in italics, ie it pre-dates when they engraved on the first draw. I guess they only had to buy stamps for those three letters too. The guys doing the stripping and plating of the sunshade commented that they had a lot (!) of trouble removing the original plating off the copper/brass. So the 18th Century platers had done a good job really! The connection rings onto the wooden barrel have been left as found, ie with plating worn off, and therefore shown as brass and copper.

Eyepiece in 1995, before replating

The eyepiece of the Dollond 8-sided scope when purchased in 1995: the maker’s name is engraved on the end face. Silver plating has worn away from the finger pressure points on the first draw, and almost completely away from the cast eyepiece housing.

The eyepiece after re-plating

The eyepiece after re-plating

The effect of re-plating of the eyepiece can then be seen in the next photo, where the flat end, which unscrews, is left as was, and the copper rim can still be seen around the edge, but the bell section is re-plated. The black cable tie is used to hang it securely on hooks in the ceiling.

The whole objective end of the telescope is fitted to the wooden barrel using one of these connection rings, on a press fit which is not that secure: how this was originally secured is unknown. I would just not poke the end over the side of a ship, or a high building, it’s just not worth the risk!

The four eyepiece lenses in two separate modules are screwed in to either end of the only draw. There is no end cap over the objective, but there is a cover over the eyepiece lens, which is contained within the eyepiece (so does not stick out and hit you on the nose!)

Objective end OD is 2.375”, with the closer connection ring 2.5”. Flat to flat dimension max on the barrel is 2.25”. Total length fully extended 51”, focussed length around 45”.

Where to find one

So, its pre-1995, and you have attended the annual London Scientific Instruments Fairs, looked in all the local antique shops: then actually you have to take some products to a photographer for PR shots, and in talking to him he mentions that he had used a telescope in a recent photoshoot, but he had a real problem getting hold of one. Eventually he had been told to go to a “Compass Adjuster” in Hamble, called R. W. Robinson, and he had loaned one. So you learn that Robinson has a shop, and as a sideline to compass adjusting on oil tankers, he sells antique nautical instruments, like telescopes, and other things.

One summer your aunt visits from the USA, and in finding somewhere to take her for the day you happen to pass by Hamble, and call in on the way to the riverside pub. Mr Robinson had this fairly beat up 8-sided telescope – it looks like it’s just come in – so I think to myself, “It will be about £350, or even more: I think I’m going to have to push the boat out to get this one”. Obviously I did not look too interested, because he only asked for £200, which I ‘reluctantly’ paid.  I then skipped all the way to the pub: Aunt Hilary did me a real favour! What’s it worth now? Well obviously I rate it highly, but I have not seen one for sale since 1995: it’s probably worth about £1000: but it’s just not one that I would ever sell. I can just relate to it.

Where/when does it fit in?

This is obviously a naval scope, for use where there is space on deck, and where the light body and magnification were useful, like Royal Navy ships, on the bridge, or for the Masters of East Indiamen I guess. It pre-dates the telescopes of around 1800, but because it uses the Dollond patented dual element objective it must be after say 1760. So a reasonable estimate is 1760-1780, around 240 years ago.

The fascination for me is that it works as well as it did when it was made in the late 1700s, after nearly 250 years, for me to spot and watch the aeroplanes flying over my house now, that were could not even have been conceived of at that time. They were looking for sails on the skyline, or hazardous rocks no-one had seen before – and maybe birds in the sky, or the moons of Saturn. But what else did the previous owners see through there, and where has it travelled to? There are no clues to that, no names stamped on the body or the wood.

It is actually perfectly balanced to enable the long body to be held up in the air, fairly stable, to find and observe an aeroplane. It has a good field of view and a good magnification. So that is what it has spent the last 20 years doing!

Accession number 25 in my lists, bought in June 1995.

2016 Update

June 2016: Heavy use for the last 20 years has stressed the joint between the objective assembly metalwork and the mounting ring onto the wooden barrel. The soldered joint between the tube behind the sunshade and this ring has failed, and the actual joint overlap is only a couple of mm. So it is dangerous to point the telescope into the air! It has gone away for re-assessment.

Oct 2016: the scope is back in use, mounted on hooks over the door so it can be grabbed on the way out into the garden. The end joint between the mounting ring and the tube leading to the objective lens is resoldered, with help from a colleague in Lancashire, so it is solid once more. A light polish has brought back the shine too.

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