Three small telescopes: Dollond, Dixey, and A. N. Other

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These three telescopes are all small and easy to carry – they could be described as “Pocket telescopes” but you would need a deep pocket, since they are all around 6” long when folded up. All with three draws, they are the shortest units that can perform reasonably well, without going as far as having a multi-draw construction, a design that gets heavier and larger in diameter in the pocket. All three of these are the same sort of length when extended, 17 to 19 inches.

The interesting part is that these three illustrate several different aspects of design, and span around 120 years in terms of date of manufacture.

  1. The Dixey scope

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So named because it is engraved “C.W. Dixey, Optician to the Queen, New Bond Street, London” on the first draw. Charles Wastell Dixey worked there (at number 3) from 1839-1862 – so the Queen was certainly Victoria – and prior to working on his own he was in partnership with his Uncle George, and supplied George IV and William IV too. Those telescopes were labelled G & C Dixey.

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This scope is of a classic design, with two lens cartridges at either end of the first draw, each with two lenses in the Schyrle-Huygens eyepiece arrangement, which is the format generally adopted for telescopes after 1800. An interesting feature of this design is that the sliders mounting each draw are sized very close, making a good seal on the outside of the smaller tube. So Dixey added air release holes in each draw, to allow the air to escape as the scope is compressed. Because they are a good fit, he did not need to cut the full flap in the slider (that can be tightened using hand pressure) to enable later adjustment, that featured in many earlier designs. However he did make two parallel cuts in the slider on each side, creating a ‘double ended flap’ that can still be squeezed to tighten a little, if needed.

The different feature here is that the scope is all brass in construction, possibly reducing the maximum OD of the unit, compared to a mahogany barrel – it is about 1.25” OD round the Barrel, but 1.375” where the brass raised around the objective area. The outside of the barrel, instead of being leather covered, which became the normal covering later, is brass, with the surface scratched in a fairly irregular pattern, then coloured in a brown shade, to simulate the appearance of wood.

The objective is a dual element lens, in an achromatic combination, held in place using a threaded ring on the inner side. It would appear that originally there was a brass protective cover fitted over the objective, this seems to have been lost. The eyepiece has a captive sliding cover in the screwed on cap. This cap holds the first lens cartridge in place, which is a push fit into the first draw.

Accession Number 238

  1. The Dollond scope

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This Dollond is engraved ‘Dollond London x15’, all in capitals with the angular, heart shaped “O” letters. This dates it to after WW2, maybe in the 1950s. So it is 100 years further on than the Dixey: but still the same style of lens construction. The view through has the same sort of magnification, but the image is much bigger, and appears to give a wider field of view.

This could be down to the larger diameter lenses used in the eyepiece section: the three draws are altogether larger diameter and feel much stronger than those in the Dixey. The barrel of the Dollond is also larger by a little, measuring 1.625” OD. The largest, third draw is 1.375”, compared to the Dixey at 1”.

Where the Dollond scores comes later: it just feels right in the hands and is easy to use. This one has the brass barrel covered in pseudo leather – which is probably real….

Accession number 45 (a long time ago!)

  1. The Other One

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There are no markings engraved on this scope. It appears to be a standard three draw, small scope from the 1800 -1850 period, but is in remarkably good condition. This is maybe because of the substantial felt lined leather case that came with it.

It is a little unusual in that it has a brass barrel, rather than a wooden one, and this is coated with a veneer or similar covering. The surface of this veneer is textured, or roughened, to a sort of matt finish. It also has a sun shade over the objective, a third the length of the barrel, with a side sliding cover assembly over the lens that can be unscrewed. If the scope is used with this lens cover in place, but with the slider open, the diameter of the window opening onto the objective lens is only about 0.75”. The eyepiece cap screws into the top of the first draw, but this has an integral long parallel section, 11mm long, that prevents the first draw pushing further into the barrel.

The Schyrle lens system

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The three lenses in the Schyrle eyepiece design. The two lenses pictured still in the cartridges are there because their threads are too tight and difficult to remove. Both cartridges pictured have external threads on the bottom, to attach to the adjacent brass fittings.

It is inside the scope that the real differences become obvious. This was a real surprise, after the outside looked like a conventional early 1800s design. First the objective is a single lens, not an achromatic doublet. Then there are only three lenses in the first draw, making up the eyepiece assembly. These are equi-spaced, by about 6cms, and the lens closest to the eyepiece cap is in fact at the far end of a 3cms long cartridge, maintaining this large distance between the observing eye and the first lens. Plus there is a ‘Field Stop’ orifice close to this lens, on the objective side. This is a different eyepiece lens system to normal, it is a Schyrle lens system. This was supposed to have not been used after about 1750, since the achromatic objective lens and the Schyrle-Huygens eyepiece then took over. The Schyrle eyepiece was popular from the late 1600s to mid 1700s, and was developed by Anton Maria Schyrleus de Rheita, a Capuchin monk in 1645.

Others, notably Chris Lord, have suggested that Schyrle three lens systems were used on telescopes well into the early part of the C19th: the construction of this scope does seem to bear that out, in that it would appear to be of the style of the early 1800s. The internal connectors between draws are conventional, but close fitting brass to brass, such that there are no cut-outs that can be pressed down to tighten the connections up.

A characteristic of the Schyrle system is that the positioning of the eye along the optic axis is fairly critical, and equally any misalignment of the lenses in the cartridges – for example by cross-threading – makes it difficult to locate the image (ie sometimes it is difficult to use the scope without just seeing a grey blurr!).

The OD of the sunshade on this scope is 1.375”, and the barrel is 1.25”. The third draw is 1” diameter, like the Dixey. But as mentioned above, the window on the objective restricts its open diameter to 0.75”, whereas the Dixey objective lens visible OD is 1.125”, so gathering more light.

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Accession number 211

Conclusion

Three scopes, all very similar in performance, but all with their different features. All are compatible with the Ramsden small scopes from 1790, and the Andy McNab scope from the C20th. It really comes down to which ones are easiest to use and carry!

The Schyrle eyepiece system used in the third model is very unusual. It was seen once before in a James Chapman octagonal telescope in my collection, but this one really did date from the late 1700s. The scope described above looks to be a much later design, and in my opinion dates from the early part of the 1800s, maybe as late as 1840. A similar design of telescope, but one which uses the Schyrle-Huygens eyepiece system with 4 lenses in the first draw, and dates from around 1850, is the John Hewitson unit described earlier.

Hewitson scope (centre)

The Hewitson scope is the smaller, second one down: this photograph shows my first three significant purchases, back in 1992

 

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Abraham three draw telescope

Jacob Abraham of Bath is a renowned maker of telescopes, and up until this year I had never been successful in acquiring a sample of his work. He was active between 1809 and 1842, and was sought out as a supplier by the Duke of Gloucester and the Duke of Wellington in that time period.  This model is a three draw unit with a mahogany barrel.

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Admittedly the photos and description on Ebay may have put other buyers off, as all the screws into the wooden barrel were missing, so it was an assembly of loose bits, and the third draw seemed to have an extra brass ring around the circumference.

Close investigation suggested it had had quite a hard working life! But once cleaned up, with the wooden barrel polished and modern screws used to hold the two end pieces into the wood (using 3/8” long screws, cut down to about 5mm), the unit is optically very good. It seems the barrel has been shortened at some point, presumably because the original screws had been pulled out of the wood too often, and there was nothing left to screw into. This then made the largest draw too long to fit into the barrel when closing the scope together, ie it hit the back of the objective lens. So to stop this potential damage the owner, or his staff, soldered a ring of copper (very neatly) around this last draw, which prevents it being pushed fully home into the barrel.

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The added copper ring round the third draw, and new screws in the barrel.

A questionable eyepiece?

The engraving on the first draw is shown below, as well as the soldering holding the eyepiece cap in position.

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As well as this mod on the third draw, the eyepiece cap has been soldered onto the end of the first draw. This cap is not necessarily the original, it may have been added to replace another cap damaged and/or lost. The shape of the cap, in terms of the tapering on the rear side, is just not what was fashionable or normal in the early 1800s. This was also the dubious aspect of a telescope discussed in an earlier story, the 8-draw Ramsden, where a correspondent pointed out that this was a fashionable shape in the  late 1800s, particularly with manufacturers in France.

DSC05531This soldered joint also means the first lens cartridge now seems to be permanently anchored in place, it does not appear to be removable any more.

Total length extended is just over 26”, and 8.75” when closed. The barrel OD is 1.75”. The draw tubes are actually in good condition, with only a few dents, in contrast to the other trauma the telescope has seen. The knurled ring on the fitting to the barrel does appear to have lost a segment of about 10 degrees, but still works fine. The missing segment can be seen on the photo above,  showing the copper ring.

Conclusion

It is still an effective telescope, and from Abraham in Bath, as the engraving says. This is also a useful size for use in today’s world.

It is worth mentioning that there were other instrument makers by the name of Abraham in other towns. For example Abraham Abraham in Liverpool, Abraham Elisha Abraham in Exeter, G & C Abraham in Sheffield, and John Aburgham Abraham also in Liverpool. This Jacob Abraham started in St Andrew’s Terrace in Bath 1809-1811. From 1830-1842 he was at 7 Bartlett Street, Bath, but also opened an office in Cheltenham. From 1833-37 this office moved to be adjoining Mr Thompson’s Pump Room in Bath, presumably to catch all the gentry taking the waters. He also developed partnerships with other instrument sellers, to presumably sell Abraham units, from bases in Glasgow, Liverpool and Manchester.

Accession number #312.

What’s it worth now? Probably £60-100.

Medium sized Dollond from 1810

This is a 3-draw Dollond with a wooden barrel, a medium sized telescope around 20” long when extended. It was acquired in August 2017, as ref #313, and is frankly the same as two previous purchases, those with Accession numbers #193 and #98.

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Dollond #313 (bottom) and #98 (top)

 

The design is classic for a medium sized scope, very similar to the early Ramsdens or the Watkins & Hill described on the last page – although earlier than that one, dating from between 1810 and 1820. The major difference in the Dollond is that the lens mounting positions in the first draw are at either end of the draw, and then at two places where the draw is split to allow access to these lenses. The photo shows the lens mounting positions along the first draw:

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At the top are the two mechanical fittings. The first draw is made from the three bits of tube, shown in the middle row. The four lenses are shown as the bottom row, they go inside the ends of the tubing sections.

The reason this design is attractive enough to buy three models is that the Dollond optics are superb. Regrettably for Dollond, the mechanical construction is not so robust: the draw tubes are relatively thin, so examples can have damaged tubes that are difficult to move, and the joints between the tubes are not soldered in place as well as is achieved in later Dollond models, or other supplier’s units. The scope ref #98 had these poor joints, and no eyepiece cap. So it is basically used as a source of spare lenses. Ref #193 was complete, although one draw was stiff and the mahogany had a crack along the length, but it worked beautifully: this one was given away.

Why buy this third model?

Ref #313 was bought to replace #193, and is complete with end cap and slider in the eyepiece, and with original screws in the barrel. The mahogany barrel has a thick layer of French polish over the original polish, and looks almost black. It does have one mechanical problem, the shoulder of the slider on the second draw is only a press fit in place.

DSC05551 mounting ringIt is interesting to note that the design of this slider and shoulder was a Dollond Patent as well, described first in around 1780 apparently! It follows good mechanical principles, and positions the mounting thread around 1” inside the tube that is the next larger on the scope. At the flange ring against the tube end, there is a shoulder making a tight fit inside the larger tube, giving the joint two separated mounting points – and so there is less likelihood of a wobble developing at the joint.

History

DSC05595 closeRegrettably no info is available. The scope was bought from a dealer in Littlehampton, West Sussex, in August 2017 – an Ebay Buy-it-Now item that was suddenly withdrawn, so I chased it. Presumably there was a failed sale, or other interest.

Accession number 313.

Watkins & Hill “Customs” scope

This telescope has all the features that you would seek for in a vintage instrument. Apart from that it is a classic design of three draw, mahogany barrel telescope, medium sized at 23” long extended, and complete with leather case – and it works well.

The first major good feature is that the maker is engraved on the first draw as Watkins & Hill, located at 5 Charing Cross, London – with the engraving being “Crofs”, in the old style of script. This Francis Watkins was the grandson of the Francis Watkins who partnered with John Dollond in taking out the original patent on the achromatic doublet, and indeed his Grandfather had run his business from these same premises, at 5 Charing Cross. In partnership with William Hill they operated from 1822 until 1856, when the business was taken over by the Elliott Brothers.

There is another engraving on the first draw, and also on the brass sleeve at the end of the wooden barrel, which is “CUSTOMS 1827”. Not only does this tell us that the telescope was made in 1827, it does indicate that it was bought by the Customs authorities for issue to their officials, presumably for use in ports or lookout towers. So just this engraving confirms the date and the first use made of the telescope.

Smaller features

The telescope has some further interesting features, first all the screws into the wooden barrel are the original screws, very neat and flush with the brass sleeves. Second the first draw has a mark around the brass to indicate the focal point for distance viewing, to assist the different users. Finally, as an antique it is good that all the screw threads run freely, so the lenses are easy to clean. The exception to this is that one of the lenses in the second cartridge, at the end of the first draw, seems to be cross threaded, and is not going to move. A possible reason for this is that while all the draws are labelled with an assembly ID of “II”, this cartridge is labelled “VI”, so possibly this has been accidentally swapped from another telescope, during a Customs cleaning session. Nevertheless the assembly works fine.

When closed the scope is 7.5” long, and it is 1.5” OD. The slider that would close the eyepiece has been removed. The mahogany of the wooden barrel is still well polished, and has a lovely colour.

Recent history

Bought on Ebay in 2017, this scope was offered earlier on Ebay but the buyer failed to pay up. On the second round I managed to win the scope – at over 20% more than the previous winning bid! It came from the estate of an antiques dealer in Nairn, Scotland, and he had owned it for at least 30 years. So possibly the scope was used by the Customs in Scotland somewhere!

Watkins & Hill

This firm was a well established supplier of good quality telescopes, and worked “By Appointment to” the Dukes of York and Clarence in the early 1800s. They were also suppliers to the East India Company and to London University. At some time they  worked in co-operation with Negretti & Zambra, according to Gloria Clifton.

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Telescope with the possibly original case

Accession number 314, bought October 2017.

Prototype variable magnification scope by Banks

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This three draw telescope is engraved as made by “Banks”, of “441 Strand, London”. It also has the letters “INVᵀ”, presumably indicating it was an inverting telescope. But it isn’t. Maybe it means an “Inverting lens” has been added to make the image the right way up! Note that the engraving is on the “left side”, ie the first letter, the B of Banks, is closest to the eyepiece. This normally indicates an early date, typically around 1800, as by 1810 the standard had changed, and the engraving was the opposite way round. The engraving also looks a little crooked, so maybe it was indeed when Banks first started making such instruments.

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In a slot in the first draw, there is the capability of moving the cartridge which holds the third lens in the scope sequence (starting from the eye) backwards and forwards, to adjust the viewed size of the viewed image (the magnification, in modern parlance). This third lens is centrally mounted in this cartridge, and it does not seem to be removable. The cartridge was presumably moved by a screw or pin positioned in the slot, attached to the cartridge: this was missing, so at the moment its place is taken by a piece of a wooden cocktail stick.

 

Does anyone have any suggestions as to what was attached to those two holes at the end of the slot? (Bearing in mind that the whole tube has to slide into the second draw, which means there is no protrubrance allowed above the OD of the tube….)

I found this very interesting, as I have mostly used pancreatic scopes, which use a similar approach, separating the two lens cartridges by a different amount, and therefore increasing the magnification. Changing the magnification also changes the focus point, so requires a slight focal adjustment. In fact, this was how my first telescope, the N&B Petrel, worked.

But what this one does is not quite as easy to define.

Banks in the Strand.

Robert Banks, or Bancks, was working at 441 Strand from 1805 to 1830. So assuming the telescope dates within this period, it would definitely pre-date all of the pancreatic scopes I have ever seen. The earliest I have found, which works very effectively, was that produced by Spencer, Browning & Co in about 1850: – see the story about the wreck of the ‘Eagle’ in 1859 on here. This later telescope is labelled as ‘Patent Pancratic’, in the engraving. Spencer, Browning & Co worked from 1840-1870.

Banks had taken a different approach to the problem, which is maybe why Spencer, Browning managed to obtain their Patent, later. Banks introduced a moveable third lens in the first draw tube, ie one of the lens pair making the second cartridge. Spencer, Browning use the separation of the two lens cartridges ie moved the third and fourth away together, further away from the eyepiece to change the magnification.

Does this work?

The Spencer, Browning variable magnification system works brilliantly, and many modern scopes use this as standard, On the other hand, I have never seen one like this Banks model before! This Banks telescope came without the pin in the sliding section. That is essential to position the third lens correctly. It also came with a 4th lens that seemed to be a substitute lens, for one that had maybe been broken in use.

So while the telescope works, but not very well, it could be much improved with the right lens in this 4th position. Or maybe it explains why this system was not adopted more widely as a variable magnification or different style of pancratic type of telescope.

Possible redesign

If the 4th lens were to be attached at the far end of the moveable cartridge, instead of in the threads provided, it would be possible to move that back and forth: then this would be the same as the pancratic principle. However, this would be a little more difficult to work with, since the focus point would move significantly as the second cartridge is moved to change magnification. At the moment, the first draw pulls out of the second, as the lens assembly substituted for the 4th lens is not big enough to make a stop within the sleeve: maybe this thread was just used for such an end stop, , and the fourth lens did move with the sliding cartridge? I still need to test this theory with some practical lens examples.

The components of the first draw are shown below:

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(The Blu-tak is to hold that lens assembly in place, it does not fit the screw-thread)

Description

DSCN6599I should mention something to give you an idea of the telescope size. As said before, it is a three draw scope, with a mahogany body. The original screws, and there are lots of them, are all still present. There are eight screws holding the objective holder into the mahogany part!

 

The first and second draws have engraved arrows, pointing towards the objective. The collar on the eyepiece end of the barrel has an engraved arrow, pointing towards the eyepiece: so these are almost certainly not giving dismantling instructions, as some people have suggested.

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Extended the scope is 28” long, and the objective lens housing is around 47mm OD. Closed up it would be 9” long. The eyepiece itself has a movable flap cover, which instead of a hole can position a ruby coloured glass over the eye hole, for when looking at the Sun presumably.  (See the picture up above).

The scope was bought in July 2017, expensively for current Ebay price levels, at £78. Seller was Bramblewood3. The seller did not understand the true purpose of the slot either. But it is certainly unique!

 

Medium sized Ramsden 3 draw telescope

This telescope is a  product from a major telescope maker from the 1790s. So, bought on Ebay, it came looking sad and unloved, held together with masking tape. But with everything in place, more or less: maybe not in the right places however.

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As received, c/w masking tape and grime

Taking it to pieces, the first draw, the eyepiece, did not work as an inverting microscope, which is always a bad sign. Then the view through the unit was rather how I imagine tunnel vision to be, a view down a long narrow tube. No real field of view available.

The name Ramsden

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The engraved first draw, after polishing

However, the telescope is a Ramsden, made maybe 1790, engraved properly (on the left side, as was the standard in 1790), and is complete with the objective lens cap. The objective lens is clean and complete, the barrel in good condition. Inside, the lenses in the first draw looked a lot the worse for interference, one stuck in the threads, and with gripper marks round one of the brass lens mounts as evidence of a lot of previous stress. It also appeared that they had been shuffled, so did not work well optically. Indeed the first draw worked as a microscope only when reversed. Then one lens was found to be jammed into the cartridge with an unusually positioned aperture assembly pressed inside the cartridge.

On removing this aperture, an unsupported unmounted lens is found: it is the necessary to start to sort them out. In this scope unusually the threads all seem to be much the same size, for the lens mounts, so that makes it easier to get them mixed up. Later the manufacturers “keyed” the lens threads to make things easily located. It transpired, after hours of trying, that this bare lens must have been a substitute for a broken one, and it was just not right. The lenses and cartridges, with their integral apertures, were returned to what seems to be the correct orientation and position by comparing the design with three other Ramsden scopes in the collection. I then realised that this one is almost identical to #51, a Ramsden bought many years ago, and reported on this website already. That report, and others, also gives the history of Ramsden in the 1790s.

Eventually the lens was replaced by a slightly smaller lens and mount from a J Webb similar scope (#263), and the whole thing fell into operation properly.  There were two ‘John Webb’ instrument makers reported by Gloria Clifton, one from 1792, and his son from 1800-1847. This telescope was labelled 408 Oxford Street, which is where Clifton says the son was based – for a short period – in 1808. Telescope #263 has other separate problems, such as a broken objective lens, so a temporary loan of this number 2 lens to the Ramsden is not a restriction. However the search continues for a suitable leens and holder that might fit the Ramsden thread, as the J Webb lens is small and only wedged in position.

Renovation

The brass polished up well, with Brasso. The main barrel is mahogany, and the old French polish scraped off easily to reveal the wood, which has a couple of longitudinal cracks, but nothing serious. This is scheduled for repolishing. The objective holder has one small screw missing, which needs to be replaced. The objective lens end-cap is present, and in good condition.  As yet the eyepiece sliding lens cover is still stuck firmly in the open position.

The pictures that follow show images before the renovation, as it was received.

 

 

Then these pics are after polishing, but before any French polish added on the barrel.

 

 

In the last picture the second lens cartridge from the bottom of the first draw can be seen: the lens facing the eye is the one that has been attacked with some form of plier grip. Also on the right, the slider on the first draw is seen, where the thread is adjacent to the knurled shoulder. Better made telescopes a few years later would have had the threaded section at the opposite end of the slider.

The telescope has ended up a fairly well made, neat and effective telescope, with really good optics, as you would expect from Ramsden.

Owners and applications?

We do not know any of this. This smaller size unit (7.5″ compacted, and 22″ extended) could have been used by a cavalry officer, or on board a sailing ship, or indeed just by a country house owner. It has not been bashed about, and appears undamaged apart from the one broken internal lens, which has had to be replaced. Overall diameter is about 1.8″ at the largest part over the objective.

Equally we have no knowledge of the ownership of the scope even recently. The Ebay seller lived in Barnard Castle in County Durham: a lot of sailors came from the northeast – Capt Cook came from Middlesbrough after all.

Thompson of Yarmouth 3 Draw

Thompson of Yarmouth. Not a name that has been echoing round the walls of Observatories or Navigators clubs for 200 years, but I found this telescope interesting, so bought it.

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Why buy this one?

Because it’s a classic three draw with a mahogany barrel and an end cap, plus a decent authentic (ie original) case, and the original screws are present on the barrel mountings. Plus it came from Great Yarmouth, where my three (maiden) Great Aunts lived, (all daughters of a WW1 Norfolk farmer, born around 1900) – but they did not date quite as far back as the telescope, as Gloria Clifton says Simon Thompson was working there in (Old) Broad Row from 1804-16 and 1830-44. So these dates tally with the style and design of the scope, and it looks a good quality item. Plus the Ebay write-up said that it works, which it certainly does, and works well.

Another reason was that it was very low cost! £24 including postage.

Inspection and cleaning#

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On arrival it looked fairly dull, and looking rust-coloured on the largest draw. It cleaned up surprisingly easily, as the pictures show, and everything was present inside – AOK in terms of lenses and other bits. It is not that used/dented, and is nicely finished. Going back to Clifton, she mentions that Thompson was a compass maker, brazier, and a telescope tube maker, as well as an Optician/optical instrument supplier. So presumably he supplied other telescope makers with tubes, and so had plenty of contacts to source the lens sets from. Not that I am aware of many other active optical instrument manufacturers in East Anglia.

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The case as well

The case is interesting: it is certainly a paper/card tube, with leather end caps well sewn onto leather wrapped around the end of the tube. The interesting part is the covering over the paper tube, which looks like a brown fish-skin of some form. Under the cap (a slightly larger tube) the inner part of the case under the cap is lined with a paper covering having some form of coloured pattern, but it is difficult to define what this is.

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History

The seller says the telescope was a present to him from his Grandmother: presumably it was passed to her from a male relative who was a seafarer, either as a profession or as a hobby, in late Victorian times maybe. But no real history is known.

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Dimensional data

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The barrel widest diameter is 1.9”. It is 9.5” closed, and 29” when fully extended. The case is 2.25” OD and 10” long. Accession Number #302, April 2017.

Bought for spare parts…

Just another mid-size two-draw telescope, bought from Ebay for spares, mainly (I thought) for the eyepiece cap, or the objective lens holder. It looked filthy and old, but had all its lenses, and a nice mahogany barrel: plus the screws looked original, holding the brass to the barrel.

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When it arrived, (as is usual) the eyepiece cap thread was totally wrong, it was too big to fit the Baleen covered Cutts telescope. The objective lens holder was too small to be any use on a 10-sided telescope restoration project, so I had failed yet again. But actually the telescope was quite nice. Only labelled “Achromatic, London”, on the sliding cover to the objective lens, it is not easy to date, it could be anywhere between 1880 and 1930.

DSCN5369It has an old design of objective mounting, and neat brass ends to the barrel. Conventional design inside, with two twin lens cartridges. One slight fault: those neat screws at the end of the second draw are actually (as ever) too long, and scrape on the slider holding the draw, when the latter is unscrewed. So they were filed down internally, to clear the brass holder.

How about a clean-up?

An afternoon polishing with Brasso had some excellent results! The black tarnishing of the draws soon fell away, and the whole telescope was transformed. Even the barrel ends are now shining.

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There were two surprises. First, on the back face of the slider positioned over the objective lens, there is a price written on there, of 14/0, ie 14 shillings, or £0.70 after decimalisation. Presumably it was sold in a second hand shop at some time after its first owner passed it on. That price would maybe have been reasonable in the 1930s.

DSCN5371The second surprise was that the second draw is fitted with a spacer so as to not let the draw out to as long as it could be – obviously the objective lens used was not as long in the focus as had been expected. No matter, at least it had been noticed, and with the spacer it now does not seem to be necessary to push the tubes in too far to gain a focus.

Some before and after pictures in relation to the polishing are shown below.

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Summary

Using the telescope, it is actually very effective, which is the main requirement after all, once you have a clean instrument. Good focus, good view and magnification. Total length open is 18.5”, closed is about 8.5”. Objective is 42mm dia, but the optically used diameter of the lens is more like 1”.

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Bought February 2017 from an Ebay seller in Felixstowe. Accession Number #299.

Gilbert & Wright scope, circa 1800

Another telescope that came from the ‘Navigation Warehouse’, at 148 Leadenhall Street, London, at around 1800. See the previous comments about the people working there in the story about the Gilbert telescope, loaded onto this website on 24 Dec 2016. This was the place to go to, if you wanted the best in telescope making expertise for a particular duty, whether astronomical or nautical.

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In fact Gilbert worked in the partnership Gregory, Gilbert & Wright – from 1790-93. This telescope however is labelled as from the Gilbert & Wright partnership, which is quoted to have operated between 1790 and 92, and again between 1802 and 1805: in both periods they were based in the Navigation Warehouse.

The design is unusual, for the date, which is 1790-1805, 210 to 223 years ago. It is presumably a specially commissioned unit for a specific task, ie it was custom built for one of their customers, to his specification.

Who was the Customer?

This telescope is a two draw, completely brass unit. It is large in size, being 37.75” (96cms) long when fully extended: the length when focussed is considerably shorter, at 30.5” (77.5cms). This does mean that completely extended, it will give a focus on an object about 5 feet away from the objective, if you might wish to do that! But an advantage of the travel of the first draw is that there is around 1cm of movement where a distant object remains in a fairly good focus to the observer. The OD of the objective lens holder is nearly 2”, actually 4.9cm.

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Fully closed up the length is 15.25”: there is no sunshade or lens cap to protect the objective lens. On the eyepiece there is a slider that moves across the lens aperture: the second smaller aperture in the slider appears to originally have had a lens or filter mounted in there. Possibly located here was a deep red ruby filter (which restricts the light passing through to the eye, and so allows the telescope user to look at the edges of the sun, or at sunspots). Whether this means it was a telescope for use in an Observatory or similar I’m not sure. The generally ‘unfinished’ nature of the construction, with no protective covering on the barrel, no sunshade etc, might also imply it was not intended for outdoor (ie shipboard) use.

The Engraving

Another possible use might have been as a “lower magnification” aiming telescope, to be attached to a larger magnification scope in an Observatory. There are no obvious mounting points for this telescope, so it must have been strapped in place in some way. But the interesting positioning of the words engraved on the first draw, around the eyepiece, implies that the normally expected reader was maybe looking normally downwards, towards the top of the eyepiece: the words are then written horizontally, to this view, on one side of the draw, but around the curve of the brass tube.

DSCN5383The actual engraving says

Gilbert&White

London

Improved Telescope

…and the positioning on the first draw can be seen from the photograph.

Further data

Inside the first draw, the two eyepiece lens cartridges are fairly conventional in design: the first one (near the eyepiece) is engraved along the length with the words “SMALLEST POWER”. Presuming that another cartridge of higher power was supplied for the telescope (a standard approach with astronomical instruments) then this would explain the need for the first draw to be pushed in a long way to achieve focus – the other (missing) eyepiece might need to work with a focal point much further out.

Each draw is marked with an arrow, plus there are two arrows on the main barrel, pointing towards the objective. In my view this indicates the desirable orientation (rotation position) of the two draws, to get the parts of the telescope lined up in the original, ‘ex-factory’ setting.

The telescope was bought on Ebay in October 2016, for £87 including carriage, and there were no other bidders. Whether it is relevant I don’t know, but it came from Dorchester. Obviously there were not many people interested in a curious design of a 215 year old telescope! It did have a well-respected name….in a curious orientation, which is why I chased it.

Accession Number #293.

JT Coppock 1960s Telescope

So, it is a real change to introduce a telescope from a different manufacturer to this website, particularly one from Leeds….in the provinces even! A centre of industry, yes, but not at all qualifying as a major shipping port – but that did not matter in the C20. It also happens to be where I lived when I first started using a telescope, also in the 1960s.

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This telescope was made by J T Coppock, of Leeds: it is a 3 draw unit, with an additional, short fourth draw which provides variable magnification. Normally referred to as ‘Pancratic’, this works by extending the distance between the two eyepiece cartridges. On this telescope the variable magnification is quoted to range between 10x (closed) through 15x, to 25x (fully extended), and these figures seem like reasonable estimates for the magnification achieved.

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Maximum length of the telescope with everything extended is 21”. Closed up it is 7.25”, and the barrel diameter is 1.625”. All the metalwork, which feels like brass, is grey in colour, as a result of some form of anodising. The barrel is sheathed in brown leather, stitched along the joint. The lens cartridges and the mounts for the draws are all very conventional in design.

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J T Coppock (Leeds) Ltd

I have not been able to find any data on an optical instrument maker named J T Coppock so far. The unit looks as though it dates from after WW2, from the 1950s or 1960s.

In the 1950s and 1960s, James T Coppock (Leeds) ltd was importing Antoria guitars from Japan, and indeed both Hank Marvin and Jeff Beck played one, as did Big Jim Sullivan when he was playing with Marty Wilde. James T. Coppock ceased trading in the early 1980s and Antoria guitar production ceased then, only to be resurrected later.

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Background Data

This telescope was bought on Ebay  in June 2016, from branneysattic – part of the drive to add some more modern examples to the collection. It is Accession Number #279