Otter Trawls

The otter trawl is a well-established and reasonably well documented bit of gear – general common knowledge says its Irish in origin, originating in freshwater loughs before making its way to English shores. Adopted in the 1880’s, it wasn’t fully utilised until the 1890’s by the surely now famous Mr Scott of Granton. If he laid claim to this invention, I have yet to find a patent for it… Nevertheless, the otter trawl became widespread within a few years.

Those that would benefit were the new steam trawlers, themselves recent additions to the fishing fleet. unlike sailing smacks, they were better able to maintain the speed that trawl doors required. Once commonplace, a multitude of variations on the trawl door and trawl itself appeared, form the functional to the fabulous. According to my database, there are 77 different patents relating to trawling between 1984 and 1914 – and most of those are just for doors. these patents are just the British ones, of course – with most of the applicants being English or Scottish. Who knows how many other patents there in European databases?

So what happened to the sailing smacks? Many simply fell into disuse, a great many were sold on to other countries, like Scandinavia. The Second World War sounded the end of the sailing smack in England and Scotland, even with the loss of vessels during that time.

GB189420323

GB189420323, a patent from 1894

Yngve Bernhardsson

Patent no. GB598097

Patent no. GB598097

I took me a long time to realise that this was the oldest patent I had for a functioning pelagic trawl –  I had misfiled it under headline floats, for some silly reason. But the niggling feeling that I was missing a piece and my Dad’s recollection of the first pelagic pair trawl had been Swedish got me to searching my database again – and up popped Yngve Bernhardsson. According to his patent, filed September 20th 1945, he was a Swedish national living on Fotö, near Göteborg in Sweden.

His patent is a short affair, 3 pages, with less than 1 and a half given over to explanation. For your pleasure I include his diagrams. He describes his trawl as having a ‘substantially rectangular mouth’, ‘tow-lines fastened at each corner of the mouth’ and that the two towing vessels ‘should be at a distance form each other that the mouth will be strained in a horizontal direction’. There is a complex affair of float and weights, which are interlinked and depicted in the diagram – apparently with some adjustable features to vary the size of the mouth. where I fell down was the lack of specificity – he, or rather the agency no doubt translating and typing up – does not mention at what depth the gear is to be deployed, or even any measurements. No doubt this is why it got filed under floats and bottom trawls.

On the upside, now I get to go through every patent and double check their classification… And that Bernhardsson beats Larsen by two months with the patents that I have at hand.

Patent Timeline – So Far…

After a fair few weeks wading through some patents, I have whittled them down to the relevant few. These are the backbone of my timeline, which will be filled in along with other documentation and whatnot. I’ve only gone up to 1959, as after that it gets a bit more convoluted and would make this entry twice as long!

The initials in brackets after the name indicates the applicant’s nationality, while the brackets after each entry have the patent number. The letters there are the country in which the patent was made. The dates are those in which the patent applications were made, not in which they were granted (anything up to 5 years after the application).

Adam GB189420323 Patent


Oct 1894 – William Adam (GB) patents a 3 boat pelagic trawl. It’s all a bit odd, but he is thinking outside the box and trying to make a functioning mid-water trawl. [GB189420323]

Nov 1898 – The first patented vertical trawl door by David Sherrit (GB). It is, however, entirely a demersal affair. But like William Adam, the idea and willingness to experiment a bit are there. [GB189824035]

Nov 1922 – Cornelis Pieter Dros (NL) patents what looks lake a trawl that can vary its depth. It is, however, not a pelagic trawl in the true sense, as the impetus for this design lies in engine and fuel efficiency, not in optimising the catch or range of the ship. [GB202887]

1925 to 1935ish – V D Ltd, a company comprising of two Frenchmen, Oscar Dahl and Jean-Baptiste Vigneron (and later on, William Black) make a series of patents for demersal trawls. The innovation here is the idea of not connecting the net directly to the trawl doors. After 1940, almost all pelagic trawl patents distance the trawl doors from the net with cables of some description.

Sep 1930 – Unlike Cornelis Dros, this patent by Marcel Simonin (FR) is specifically designed to be used at whatever depth is desired. The design is quite simple and has a very narrow mouth with the net being directly connected to the horizontal trawl doors. [GB356493]

Dec 1938 – Franz Suberkrub, along with Ernst Karl Ludwig Roscher and Kurt Jaeger Hansing (all DE) patent their vertical trawl door. Made of wood and metal fittings, the door is made for demersal use. [GB523452]

Dec 1948 – Robert Larsen (DK) patents his two-boat pelagic trawl in Denmk.

Nov 1949 – Robert Larsen’s (DK) first patent outside Denmark is made in Ireland – the two-boat pelagic trawl, as before. [IE019864]

Nov 1949 – Karl-Hugo Larsson (SE) was, judging by the amount of research he published and was involved in, a key and influential figure in the development of pelagic trawling. This is his patent for a one-boat pelagic trawl with vertical trawl doors. The vertical doors in this case are curved, very much in the manner of Suberkrub’s patents. [GB670222]

Larsson’s patent GB670222

Nov 1949 – Robert Larsen (DK) makes a British patent for his two-boat trawl. [GB695361]

Nov 1950 – Sterner Persson (SE) patents his trawl capable of functioning at different depths – primarily a pelagic trawl. The trawl has three trawl doors – two at each side, and one from the ground rope to keep the net open. The trawl doors in the more traditional location are vertically orientated. [GB682824]

Feb 1952 – Jon Sigurdsson (IS) patents a pelagic trawl, with a third trawl door attached to the ground rope and horizontal trawl doors. [GB699206]

Aug 1952 – Another Icelander, Agnar Gudmundsson Bredfjord, patents a pelagic trawl. This trawl has the hallmarks of a modern pelagic trawl and has vertical trawl doors. His patent states that one of his reasons for pelagic, rather than bottom fishing, is to not disturb the vegetation and small fry that may be on the seabed. [US2771702]

Breidfjord’s patent, US2771702. By far and away the prettiest, too.

Nov 1954 – Robert Larsen (DK) isn’t taking any chances; this is his Canadian patent for the two-boat trawl. [CA507700]

Dec 1955 – Karl-Hugo Larsson (SE), who made his one-boat pelagic trawl patent a year or so after Robert Larsen in Britain follows his lead and makes his patent in Canada as well. [CA519107]

May 1957 – This time a man of unknown nationality, Donald S Johnson, has his invention patented on his behalf by the Dominion Textile Company, Canada. The patent describes a one-boat pelagic trawl with what appears to horizontal, tubular trawl doors. [CA541497]

Dec 1958 – Moises Larrea Esesumaga (PT) patents a trawl for working at varying depths, from surface through to demersal The trawl has no trawl doors, instead relying on four kites at each corner to hold the net open – the shape of the mouth of the net being controlled by ‘guides’. [GB911666]

GB911666, Esesumaga’s patent

June 1959 – Franz Suberkrub makes a solo patent, for the vertical trawl door. Now designed for pelagic rather than demersal trawling, this door is now a sleeker, version of the 1938 version, no longer being made of wood. [US3079720]

So that’s the boiled down version – the real one is a lot longer and a bit more complicated. But at least you can all see the basics from which I am expanding and researching from. That and having to teach every word-processing programme I come across the word ‘demersal’. Non of the seem to recognise it!

Trawl Doors Before Trawl Doors

Before trawl doors there were, well, no trawl doors. History tells us that commercial fishing went kind of from the beam trawl to otter trawl. That’s not to say that all the other methods aren’t important, but my focus – being pelagic – does have trawl doors as the keystone in the whole arrangement. So trawl doors is what I have to look at. If you’ve perused some of my previous posts, you couldn’t be blamed for thinking I have trawl doors on the brain. this, of course, is my excuse for bringing you three more examples from the archive. These three represent something different, though. These three are all early attempts to keep the mouth of a trawl open without beams – and without doors.

The earliest patent is GB189730188, dating from 1897. Here, messers Lewis Levi and George Cartwright, Brass Finisher and Hotel Keeper respectively and both of Hull, clearly think otter boards are a waste of time. Their intention is to do away with both beams and otter boards, by way of a a watertight tube that runs around the mouth of the trawl. The idea is that by using “hydraulic pressure, air pressure or the like” to inflate this tube with either air or a liquid the mouth of the net stays open. What the patent doesn’t explain particularly well is how this is meant to be weighted or protected from the rigours of the seabed…

GB189730188 - the hydraulic tube mouth opener...


One patent that bemused me no end is this one: US649581, dating to 1900. An American patent, this one appears to be a rigid frame, which will hold the mouth of the net open. The inventor, John G Landman, a resident of Brooklyn, New York, states that the purpose of his invention is the “provision of a simple, cheap and effective spreading-frame”. His object, as such, is economy and simplicity.

US649581, the net-spreading frame from Brooklyn, New York

Last but not least, I find myself gazing at a British patent whose applicant hails from Japan: GB102554. Dating to 1916, this patent professes that it “relates to otter boards and the like for steam trawling apparatus of the type where the rear ends of the otter boards or the like are attached to the head and foot ropes of the trawler net….” I would quote more, but the rest of the sentence runs on for another paragraph or so. The long and the short of it is that the otter board is not a board but an arrangement of canvas covered ‘ribs’.

GB102554, the alternative otter board, comprising mainly of canvas and 'ribs' of metal.

What caught my eye was the name and nationality of the inventor – “Tsunejiro Shirato, of Misakino-machi, City of Shimonoseki, Empire of Japan, Engineer…” Certainly not the phrasing we would expect in more modern, PC-stricken documents. But it’s certainly interesting to consider what and why Shirato felt the need to patent his invention all the way in Britain, why he didn’t do so in the USA and the research/experimentation that he conducted that resulted in his belief in his invention.

Otter Boards & Little Wheels…

Well, let’s not kid around  – this PhD malarky consists of a lot of boring stuff and a decent amount of technical stuff, all interspersed with the very interesting and bloomin’ weird. and that’s just the application paperwork…

Well, I am still in patent limbo – and as a result have come to embrace it. As a result, i am going to post up some of the more interesting and bizarre of the applications I have come across. the three I am looking at right now are the earliest patents available for otter boards, picked not because of their date, but because of their specific peculiarity: wheels. Yes, they have wheels. Back in the day there are numerous and varied patents for otter boards, several of which predate these – but these are special. these have wheels.

And not just any wheels: Samuel Ling and William Robbens’ 1899 patent is wonderful in its simplicity. two small casters are attached to the bottom edge of the boards – “to facilitate the use of the boards”. these two, both smack owners from Lowestoft, also the the time to explain that the the current invention can be expanded – that four casters can be attached, “so as to support the board in an upright position”.

(Patent number GB189907260)

Another gem from this archive is also form 1899. Two residents from Hull – an engineer and a boilermaker – Henry Ramsden Mortell and Alexander Robb made their otter board that is more or less a wheel. this wheel can be fitted to the centre of an otter board, should one feel traditional, but the wheel is the story here. A lot of thought clearly went in to the design, as the primary concern is not just the spread of the trawl but also potential resistance and weight. the goal here, it states, is to prevent excess fuel consumption as well as wear and tear on engines and equipment. Their idea may have been verging on daft, but they had serious motivation and a clear goal.


(Patent number GB189915702)

The last in this series is not particularly spectacular or challenging; another 1899 patent with casters on the brain. This one, by Thomas Frederick Adamson and Edward Clarke, Ship’s Store Merchant and Engineer respectively, both of South Shields, made the simplest one I’ve seen yet. These little casters are fitted to the bottom edge of the otter board. they slot in aways and angled, so as not to impede the angle of the otter board to the boat. A simple idea, neatly expressed. Just a shame it would all never really work…


(Patent number GB189924174)

Before I scurry off to do some real work, I have a big thank you to announce to Victor and Linda Strange of TorNet, in Iceland. They have made a much appreciated contribution to my study and ongoing research!

http://www.tornet.is/


Patents… Continued

It’s been a little while since I posted – largely because I have been engulfed by a pile a paperwork that I can say, without even a hint of a fib, is bigger than my head. I made the mistake of printing off an enormous pile of patents with the intention of sorting and reading them in a few days. Having severely underestimated my speed reading ability and making some sacrifices, two weeks later I am facing the last 50 or so. This coincided with another set of papers, a pile of potentially relevant reports in pelagic fisheries in Britain from the 1950’s and 1960’s. Once the patents are entered into my database and put to one side I can finally look at them! It also means that I can stop wittering on about patents to whoever will stand still long enough to listen.

For now I can use the look at the database and see more than a few obvious trends. Last time I posted about profession, but this is a limited, if intriguing window to the past. After the First World War profession is no longer stated on patent applications, being replaced, it seems, with a declaration of the applicant’s nationality. Looking instead at the addresses of those applying I can see straight away some familiar names – Grimsby, Hull, Aberdeen, Fleetwood and Milford Haven. These are by far and away the most represented, with a smattering of Edinburgh, Gravesend and the Tyne area. This is also something I will try and pursue a little further, as I would like to see if the number and concentration of applicants reflect the status and economic power of the ports and harbours they come from. But what caught my eye when I scrolled through my work so far was how few examples there are of vertical trawl doors.

Only four examples popped up. these applications were made in 1897, 1898, 1938 and 1959. That last two were made by Franz Süberkrüb, while the earlier come from very different places. The 1897 patent as made by “… Johann Cohrs of Grosse Elbestrasse, Altona-on-the-Elbe, German Empire, Fish Auctioneer…” Well, for a start ‘German Empire’ is very much a voice from the past that many would like to forget. But the patent itself is intriguing, albeit somewhat irrelevant to the overall Pelagic theme, as he puts in with his description of the ‘heavy rollers… for facilitating the passage of otter boards over the ground’. So Johann Cohrs starts off very promising, but ends up as a side note in the overall assessment of trawl doors. His contemporary, David Sherrit, and Engineer from Aberdeen, takes a completely different approach to the vertical trawl board. His is very much a door – attached in a manner above the net – and as such does not need to touch the ground. Of course, on of the things that I have to keep in mid when looking at all this, is that there might not be any documentation for something considered completely normal – so when David Sherrit also states they may be “… ordinary otter boards…”, I could be missing out something here. Ultimately, however, these two are footnotes in the progression of technology that led to the rise of the pelagic fisheries.

It is the patents by Süberkrüb that lead us back to familiar pelagic territory. First, there is Süberkrüb’s 1938 patent application for vertical, curved trawl doors. Although I have no doubt that a proper fisherman would look at the design, I found myself drawn to the individual details: firstly, that the patent is shared with two other inventors and secondly, that the application was made in 1938 – and accepted in 1940. Given that all three applicants are from the Hamburg area and declared as German citizens, it leads me to wonder what was going on in the fisheries at the outbreak of the Second World War, and the more precise events that surround this patent, at this time. It’s certainly something I mean to explore as much as possible in the next few months. His later, 1959 application is more telling in its differences. Süberkrüb makes this application alone. Like his 1938 patent, he lives in Hamburg – and I wonder what happened to his colleagues. The 1938 patent was made in Britain, the 1959 one in the USA. The design, the principles behind the two patents are largely similar, but what is striking is the change in materials. In 1938, it was wood and metal fittings, formed to make a curved panel. By 1959, the wood is gone – “… wooden otter boards are unsuitable…” – and the suggestion is for metal or even plastic. On paper it looks very sleek and modern, with a sparse two page explanation paring down the science behind it.

One of the things i am looking forward to doing with this project is looking at more than the technology and politics. I am making it very much a key part of this research to look closer, not just at the historical facts but the personal stories of the individuals of the people who made historical fact. At the very least, it’s going to be an interesting journey, regardless of absolute relevance in the end.

Süberkrüb's 1938 patent no. GB523452

Süberkrüb's 1959 patent no. US3079720

Tthe Boilermaker, the Minister and the Gentleman

So here I am, still wading through patents – and covering two aspects of research at the same time. By focusing on the earliest patents, from 1880 to 1910, I am covering both the very early pelagic-related inventions and the vast number of ideas put to paper regarding all commercial fishing technology, thus exploring the background and lead up to what is now the commercial fishing industry. On the research side, I have now a small database with nearly 140 entries – and with only a 7 more decades to go…

And they are an interesting bunch, the earliest patent applicants; at first I was only looking at the actual inventions and their potential relevance. As I started the database (to track dates, names and nationality) I found myself adding a few new fields, some relevant, others just out of interest. Addresses – that is to say, place of residence of the applicants – revealed some obvious trends, like the high amount of applicants from Aberdeen, Hull, Grimsby and Gravesend. Osgodsby in Yorkshire had a lone representative, John Phillips, who made several patents regarding kites in the 1950’s and the The Boston Deep Sea Fishing and Ice Company Ltd of Boston, Lincolnshire made a patent in 1899 for circular (and thus rotating) trawl boards. It would be curious diversion, to find out more about them. Most applicants, however, are individuals, not companies.

In the earlier patents profession is a required field, which I also put into my database. This is less relevant but rather more interesting, such as James Pearson, resident of London, who made two patents in the late 1890’s – both for trawl nets. One of these patents, made with William Wood, is for “wing inflators”, a complex and rather odd-looking contraption than can be best described as a variation on trawl doors. the patent itself is interesting – and even more so when detailed reading tells us that James Pearson is a Minister of the Presbyterian Church of England and William Wood an Advertising Agent. These two are not alone in their seemingly irrelevant professions; Adam Scott in 1895 is stated as a Chemical Engineer, George Irvin in 1899 is simply listed as “Gentleman”, Harry Kyle in 1900 as a Doctor of Science, while the 1897 patent of Lewis Levi and George Cartwright are listed resepctively as Brass finisher and Hotel Keeper.

With these patents mentioned above I find myself trying to see whether these are real, serious applications to furthering technology, or some potentially rather odd people with too much free time on the hands and access to public transport. Given the detail, the overlap in basic ideas and principles, it unlikely that they are crackpot inventors. Nevertheless a lot more research is needed to make sure I don’t overlook a hidden historical gem just because the inventor has listed himself as simply “Manufacturer”, without elaboration as to exactly what it is he is inventing. And I do men he, of course. So far, only the men have made any patents. Not that I have any issue with that – it will just make the first female to do so a more intriguing character to investigate.

Profession on these patents isn’t just about the unusual or seemingly irrelevant; it also tells me a lot about the other applicants. Invention in the fishing industry was clearly one in which a lot of people were interested and involved in. Inventors range from Ships Captain, Smack Owner and Engineers to Naval Architect, Joiners, Blacksmiths and Fish Merchants. A good few Ships Husbands and Boat and Ship Builders crop up, along with a lone Master Mariner, Rope Maker and a Boilermaker. All of these patents are filed by so many trades in and surrounding the fishing industry of the time – but only one of these so far is content to describe himself as a Fisherman. Frederick Myroft of Grimsby patented in 1902 what I can best describe as a trawl board for the headline of a net. While many are also content to describe themselves as Owners or Captains,  towards the end of the 1910’s this becomes Steam Trawler Owner or Steam Trawler Captain – something of greater relevance to my study, as the mechanisation of ships and equipments made pelagic trawling a lot easier (to say the least).

I could waffle on for a lot more about what these patents say, not just in inventions but the people and society who made them. But I have a 7 more decades of reading to do – and the 40’s and 50’s are going to be very interesting indeed!