Welcome to the web site of Nicolàs de Hilster
I am a hydrographic surveyor by education and the founding owner of Starmountain Survey & Consultancy BV, a company in specialised measurements in the hydrographic and geodetic field. Main field of work are offset surveys and calibrations of hydrographic survey vessels and lecturing at the bachelor hydrography course at the Maritime Institute Willem Barentsz on the isle of Terschelling, the Netherlands. In my private life I am a collector and independent researcher of nautical and geodetic instruments. The main focus of my research lies on instruments used for latitude determination at sea from Thomas Harriot to John Hadley and their contemporaries. Part of my research is creating reconstructions and replica's of the instruments and to use them in the field for a better understanding of their capabilities. In addition to that I am interested in geodetic instruments and their development from Martin Waldseemüller to Heinrich Wild and their contemporaries. This web site gives an overview of a part of my collection of nautical and geodetic instruments and the research on them, the works I consulted and collected on the topic and papers I published. The current page is my slowly but surely growing blog.
Blog:
July 2012:
This month an instrument of legendary proportions (at least here in the Netherlands) was donated to my collection. This instrument, the SAT/SAGEM Minilir was the first autotracking total station and has been used to position vessels at, and piers of, the Eastern Scheldt Storm Surge Barrier during its construction in the 1980s. The instrument was initially combined with a Geodimeter AGA 112 electronic distance meter (EDM), which was later replaced by the IBEO Fennel PS 50 EDM. Depending on the EDM used the system became known as either the AGA/Minilir or Fennel/Minilir.
May 2012:
After having found Heinrich Wild's first two theodolites he designed for (or had design features by him) for Carl Zeiss, the Carl Zeiss Th1 and Carl Zeiss RTh II, it was now time to get Wild's first own theodolite, the archetype T2. A befriended collector kindly pointed me to it when this one became available on an on-line auction site and is how the instrument ended up in the collection.
April 2012:
Recently we have moved to a temporary home causing some silence on my blog. Last April I was informed that an 1835 66ft standard chain by Doyle & Son came up for sale on an auction site. Having two 'normal' chains in my collection by Lerebours (or at least French) and Chesterman made me decide to add this rarity to it. It came in a box and is invested with hallmarks as can be seen on adjacent picture.
October 2011:
As may have been noticed I have switched off my weather cam some months ago. Instead I wanted to use that area on my web site for an other set of instruments and tools I have in my collection. Under the header Survey Tools I will add steel tapes, chains, clinometers and other tools used in surveying. The first to be added are an early 20th century J.B. Tibaut Desimpelaere 10 metres steel tape, a mid 19th century 10 metres chain, possibly by Lerebours, and an early 20th century 100 feet Chesterman chain.
September 2011:
Strange how things can go when you use and collect older instruments. It was only last May when I found a famous theodolite designed by Heinrich Wild during his years as manager of the Geo department of Carl Zeiss, the Carl Zeiss Th1. Now I laid my hands on a Carl Zeiss RThII, the first theodolite to feature Heinrich Wild's patents.
August 2011:
A few weeks after I bought two 1960s Wild N3's for a product development within my company, a client who heard about it decided to donate this latest model Wild N3 to my collection. Judging from the impeccable state it is in, the instrument has spent little time in the field. The instrument was the latest version of the Wild N3 and design-wise it is very similar to the Wild TC1 in my collection which also dates from the same period.
July 2011:
For a new product development of my company I needed two Wild Heerbrugg N3 levels. A geodetic instrument dealer here in the Netherlands had two them in stock; one from about 1962 (serial 106547) and this one from 1961. Despite being the oldest of the two it is in an amazing brand new condition, due to the fact that it has only been used for educational and research purposes at the Delft University.
May 2011:
This month I was at the workshop of a Leica dealer here in the Netherlands in an attempt to get the Wild Heerbrugg TC1 repaired. Although sadly enough the repair has failed, the discussions about early geodetic instruments lead to the discovery of a Carl Zeiss Th1 optical theodolite on E-bay. This particular instrument was the first theodolite that combined glass circles with an optical plan parallel coincidence reading mechanism and marked the dawn of a new era in theodolite design and influence later models like the Wild Heerbrugg T2 and T3. After a few days of negotiations the instrument finally ended up in my collection.
April 2011:
I have added a new instrument to my collection. This time I obtained a pantometer through an auction web site. The instrument combines the functions of an equerre with those of a graphometer or Pseudo Dutch Circle. Having 'worked' in Argentina the instrument has seen more of the world that I did...
March 2011:
Recently a collector came to me with the request to restore an early 18th century Davis Quadrant. The instrument was bought without any vanes, but in style it was remarkably similar to the ones I make and are based on an original in the National Maritime Museum in Greenwich. The Davis Quadrant has a declination scale with English inscriptions and based on a Julian calendar, which indicates it was made before 2 September 1752 (the date the British turned to the Julian calendar). Using original woods and ageing techniques all four vanes were recreated in the style of the instrument (see pictures 19 - 21 for the fully restored Davis Quadrant).
December 2010:
This 18th century Surveyor's Cross or Pseudo Holland Circle I found while scouring the internet for antiques dealers. The instrument is a simplified form of the Holland Circle (Hollandse cirkel). Compared to it the instrument lacks a compass, the suspension ring for vertical measurements, and it has been engraved in degrees only. Holland Circles also had trigonometrical scales (sine, tangent and secant) and sometimes a Polygon scale similar to the one on the 17th century surveyor's cross in my collection. Due to its simplified form the instrument is sometimes referred to as a Pseudo Holland Circle.
October 2010:
From 9 October 2010 until 6 February 2011 the maritime museum in Vlissingen, muZEEum, features the exhibition Geheime Kaarten in Zeeland, Getekend voor de VOC (Secret Maps in Zeeland, drawn by the VOC). The exhibit shows maps and instruments made and used by the Zeeland Chamber of the VOC. Being mainly used by Zeeland chamber of the VOC one of my reconstructions of the spiegelboog (mirror-staff) will be part of the exhibition. The spiegelboog - invented in 1660 by Joost van Breen, the later examiner of the mates of the Zeeland chamber of the VOC - was the first reflecting navigational instrument (picture at the right by Esther Boogaard).
September 2010:
With a generous donation by my family for my birthday I could make this long lasting wish come true; adding a Wild Heerbrugg T3 theodolite to my collection (at the right on the picture). A search on the internet initially resulted in two instruments in the US, but both were incomplete. Finally I found myself this complete early T3 (1939). In addition to that I am trying to get all levels in my collection on-line as well. The first of them is the 1951 Wild Heerbrugg N2 (at the left on the picture). It came into my collection as part of a generous donation by a former colleague in 2008. Up to now I lacked the time to get all instruments from that donation on-line, trying to get it done now though...
June 2010:
This month my article on the demi-cross was published in bulletin 105 of the Scientific Instrument Society. The article is available as download from the demi-cross page.
May 2010:
In 2006 I met clockmaker Günther Oestmann of Ars Mechanica at the National Maritime Museum in Greenwich. He then had a talk on casting an astrolabe, which he had recently done. After the talk we discussed the possibility to create an Iberian astrolabe for my collection. I created an AutoCAD drawing based on the dimensions of an 1588 original, which Günther used to have the body cast. This month we met again during the A Sense Of Direction symposium and I was presented the astrolabe which he had made. On the adjacent picture Günther, who stands on the right, hands over the astrolabe to me. On the conference I presented a paper on the early development of the Davis Quadrant, which will be published later.
November 2009:
The National Museums of Scotland invited me to display my collection of early navigational instruments at the launch of the 350th anniversary of the Royal Society, held in the National Museum of Scotland on 30 November, 2009. The image shows my instruments next to the replica's the museum was able to commission thanks to funding by The Royal Society. The inset shows a full view of the table with from left to right: Master Hood's cross-staff, the Kronan Cross-staff, the spiegelboog (mirror-staff), instruments for electrical experiments, the demi-cross, a weather glass, telescope and lodestone, the hoekboog (double triangle), a globe, the Davis quadrant, a magic lantern and the Hasebroek cross-staff.
October 2009:
Although still available from Cassens & Plath, the price was that high - about half their top model sextant - that I decided to recreate the pentagon prism attachment that once belonged to my Cassens & Plath geodetic sextant. I have spent quite a few enjoyable hours in my garage, cutting, drilling and heating some brass, the result of which can be seen here. Together with the pentagon prism attachment I made a new adjustment tool that is long enough to get beyond it and all for just little over the additional costs of their mahogani cases.
September 2009:
A friend of mine tipped me off that an early surveyor's cross was for sale on a Dutch auction site. After a week of bidding it finally came into my hands at a very decent price. When I collected it (some 200 kilometres away from here, close to were this friend lives) my friend asked me whether I would appreciate a Wild TC1 total station as well as a donation to my collection. Of course this was an offer to good to be true, so the collection has grown with another two land survey instruments. In addition to that I cleaned a Cassens & Plath geodetic sextant that I already had in my possession since last year. As the instrument was extremely corroded it took a mere five hours to get it a bit neat again.
August 2009:
Almost a year after I obtained the Keuffel & Esser transit I finally had time to repair the missing wire from its reticle. The reticle of this instrument was made of spiders cobweb of which only the horizontal stadia wires survived. The picture at the right shows the cross-orbweaver that kindly donated one of his threads through the repaired telescope of the transit. Repairing the cross-hair of the reticle took about three hours. See figures 15 to 20 on the K&E transit page on how this was done.
July 2009:
After four years of research I finally made a reconstruction of yet another early navigational instrument: the hoekboog (double triangle). It was developed in the early 17th century, around the same time as the demi-cross and mainly used by Dutch navigators.
June 2009:
During (or rather at the end of) the 2009 SIS conference in Paris, France I visited this flea market where I found this old box with interesting content. Not only did it contain an equerre, but also an Egault type level by Secrétan à Paris. The level was remarkably complete and in very good condition. In addition to that this month my article on Master Hood's cross-staff was published in SIS Bulletin 101.
May 2009:
Another superb donation to my collection in 2009 next to the donation of the Kern E1 total station. Being a left-over in an inventory, the previous owner had little use for this Leica NA2 with Wild GPM3 parallel plate micrometer and decided it would fit better in my collection than on the market. This level was originally developed by Wild Heerbrugg and was one of best they ever made with only the Wild N3 being more accurate.
April 2009:
I have added three theodolites to the land survey section which I received from (or swapped with) former colleagues last year; an early (1962) Wild T2, an Askania Tu 400 and an early Carl Zeiss Th42 (the latter has left the colection in 2011). These instruments have an angular resolution of 0.0002gon, 0.001gon and 0.01gon respectively, so quite different instruments for different purposes. Although I am not sure about the manufacturing years of the last two instruments it seems in this case that by coincidence the accuracy is disproportionate with the manufacturing year (so the older, the better).
February 2009:
A colleague donated this instrument to my collection, for which I am very grateful. The instrument is a Kern E1 total station, one of the first total stations made. It has served many years in the field and now finally retires in my collection while still in perfect working order.
November 2008:
A test bid on the internet accidentally resulted in this Keuffel & Esser Preliminary Survey Transit (model 5129N). I was only one dollar above the reserve (which was very reasonable) and nobody was feeling like overbidding me (perhaps because of the world wide financial crisis?). Never mind, I am happy with this new addition!
October 2008:
Through a Dutch auction site I found myself these two bottles. Together they form a level instrument for hydrostatic levelling. Once bought by Corus for shaft alignment, they were discarded some 20 years ago and subsequently taken home by one of their employees.
September 2008:
Another Ebay item: Again after searching for it for several years I finally got myself a water bottle level. This is as basic as it can be; two communicating bottles of water, attached to each other by a brass tube.
July 2008:
A lucky bid on Ebay: After searching for it for several years I finally got myself a Roelofs Solar prism for my Wild T2. Although of Dutch origin, this one came all the way from Fairbanks, Alaska. The Roelofs Prism can be used for sun shots, which in itself are used to determine true north in the field. In my case I use the Roelofs Prism for gyro calibrations. Using a simple spreadsheet on my mobile phone I get accuracies of about 0.005 degrees, which is more than enough for a proper calibration as the gyros that I calibrate (Fibre Optic Gyro's or FOG's) have an accuracy of about 0.3 degrees.
May 2008:
The annual study conference of the Scientific Instrument Society was held in The Netherlands from 6th until 9th May, 2008. They not only visited several museums, but also had the chance to see the work of Tatjana van Vark in Ede and my instruments and dividing methods in Utrecht at the Utrecht University Museum (Picture by Otto van Poelje, Chair of the Oughtred Society Award, The Netherlands).
March 2008:
Last year I was commissioned to create a set of early 17th century navigational instruments for a new museum in Hirado, Japan. The set consisted of a demi-cross, a cross-staff modelled after the one found on board of the Kronan, a traverse board and a chip log with hour glass.
November 2007:
Another reconstruction finished: Master Hood's cross-staff from 1590, the start of a new development in navigational instruments. This instrument has been described in period literature during the period 1590 - 1622 and was used for shadow observations of the sun in a forward manner and for land surveying.
October 2007:
It is finally finished: the reconstruction of a 1621 demi-cross, an early Dutch backstaff after an instrument by Sir John Davis. This instrument has been described in period literature during the period 1621 - 1693 and was used for backward observations of the sun.
September 2007:
After a long period of no updates on my web site I finally have some news. To start with I found myself a new object: a Range Finder Cotton Type MKII by E.R. Watts & Son, London. This instrument was used some one hundred years ago to measure distance to objects at sea that have known dimensions. The other news is that since November last year I have been researching the development of the Davis Quadrant. During this research I stumbled upon blue-print like sketches of an instrument from 1621 called the Demi-Cross. With the reconstruction of it nearing it's completion I will soon upload a page on this instrument.
November 2006:
At the 2006 Navigational instruments as a source of historic information symposium at the National Maritime Museum in Greenwich I presented the spiegelboog (Mirror-staff in English) to an interested audience. On this picture by Jeremey Spencer I am explaining the instrument to Wouter Heijveld (Curator of Navigational Instruments Rotterdam Maritime Museum), Gloria Clifton (Head of Royal Observatory, Greenwich) and Richard Dunn (Curator of History of Navigation, National Maritime Museum, Greenwich).
September 2006:
Finally after two years of research a complete article on the spiegelboog (Mirror-staff in English) was published in the Bulletin of the Scientific Instruments Society. The Scientific Instrument Society (SIS) was formed in April 1983 to bring together people with a specialist interest in scientific instruments, ranging from precious antiques to electronic devices only recently out of production. The Society has a truly international membership offering those who join the chance to link up with instrument devotees across the world.
August 2006:
My latest find: a brass octant by T.S. & J.D. Negus, New York. In January 2007 I have been in contact with the great great granddaughter of John Davidson Negus. Much of the details on the Negus page originate from her research.
January 2006:
Delivered two cross-staffs to museums: one ebony cross-staff at the Archenhold Observatorium in Berlin, Germany and the copy of the Kronan cross-staff to the Kalmar Läns Museum in Kalmar, Sweden.
November 2005:
My latest project is finished: creating a copy of the Kronan cross-staff. In the meanwhile I'm starting research on another long gone navigational instrument: the Dutch version of the Davis quadrant: the hoekboog (double triangle).
October 2005:
On the 22nd of October 2005 I presented a paper on the Reconstruction of the spiegelboog at the 'Who needs scientific instruments?' conference at museum Boerhaave in Leiden, The Netherlands. On the 11th we did a field test with my replica's.
September 2005:
My latest find: a Stadimeter. This instrument was used to measure the distance to ships at sea and is based on a sextant.
May 2005:
Combined my holiday with a visit to the Kalmar Läns Mmuseum where I met Lars Einarsson and Max Jahrehorn. They allowed me to measure the Kronan cross-staff which I will build later this year.
April 2005:
A project is finished: The reconstruction of a spiegelboog (Mirror-staff in English), an instrument by Joost van Breen. I also included a page where you can check if the staff in your possession is a spiegelboog or cross-staff.
Click here if you have any remarks and or questions.