Special Roads

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Sometimes I’ve seen signs on dual carriageways and motorways that seem to specify a speed limit that’s the same as the national speed limit (i.e. 60 or 70 mph for most vehicles, depending on the type of road), which seem a bit… pointless? Today I learned why they’re there, and figured I’d share with you!

Google Street View photo from the A1 East of Edinburgh, showing a blue "No motor cycles under 50cc, moped,s invalid carriages and animals" sign alongside a 70mph sign.
The first time I saw this sign, on the A1 near Edinburgh, I wondered why it wasn’t just a national speed limit/derestriction sign. Now I know.

To get there, we need a history lesson.

As early as the 1930s, it was becoming clear that Britain might one day need a network of high-speed, motor-vehicle-only roads: motorways. The first experimental part of this network would be the Preston By-pass1.

Monochome photograph showing construction of bridge support pillars.
Construction halted on several occasions owing to heavy rain, and only six weeks after opening the road needed to be closed for resurfacing after the discovery that water had penetrated the material.

Construction wouldn’t actually begin until the 1950s, and it wasn’t just the Second World War that got in the way: there was a legislative challenge too.

When the Preston By-pass was first conceived, there was no legal recognition for roads that restricted the types of traffic that were permitted to drive on them. If a public highway were built, it would have to allow pedestrians, cyclists, and equestrians, which would doubtless undermine the point of the exercise! Before it could be built, the government needed to pass the Special Roads Act 1949, which enabled the designation of public roads as “special roads”, to which entry could be limited to certain classes of vehicles2.

Monochrome photograph showing a sign at the entrance to the Preston By-pass, reading: 'Motorway. NO L-drivers, mopeds, motorcycles under 50cc., invalid-carriages, pedal-cycles, pedestrians, animals'.
The original motorways had to spell out the regulations at their junctions.

If you don’t check your sources carefully when you research the history of special roads, you might be taken in by articles that state that special roads are “now known as motorways”, which isn’t quite true. All motorways are special roads, by definition, but not all special roads are motorways.

There’s maybe a dozen or more non-motorway special roads, based on research by Pathetic Motorways (whose site was amazingly informative on this entire subject). They tend to be used in places where something is like a motorway, but can’t quite be a motorway. In Manchester, a couple of the A57(M)’s sliproads have pedestrian crossings and so have to be designated special roads rather than motorways, for example3.

1968 Manchester City Council planning document showing their proposed new special roads.
“…is hereby varied by adding Class IX of the Classes of Traffic set out in Schedule 4 to the Highways Act 1980 as a class of traffic permitted to use those lengths of the special roads described in the Schedule to this Scheme and which…” /snoring sounds intensify/

Now we know what special roads are, that we might find them all over the place, and that they can superficially look like motorways, let’s talk about speed limits.

The Road Traffic Act 1934 introduced the concept of a 30mph “national speed limit” in built-up areas, which is still in force today. But outside of urban areas there was no speed limit. Perhaps there didn’t need to be, while cars were still relatively slow, but automobiles became increasingly powerful. The fastest speed ever legally achieved on a British motorway came in 1964 during a test by AC Cars, when driver Jack Sears reached 185mph.

Cyclists alongside a 'motorway' river bridge lane.
The “M48” Severn Bridge is another example of a special road that appears to be part of a motorway. The cycle lane and footpath (which is not separated from the main carriageway by more than a fence) is the giveaway that it’s not truly a “motorway” but a general-case special road.

In the late 1960s an experiment was run in setting a speed limit on motorways of 70mph. Then the experiment was extended. Then the regulation was made permanent.

There’ve been changes since then, e.g. to prohibit HGVs from going faster than 60mph, but fundamentally this is where Britain’s national speed limit on motorways comes from.

The Motorways Traffic (Speed Limit) (England) Regulations 1967, highlighting "3. No person shall drive a motor vehicle on a motorway at a speed greater than 70 miles per hour".
I assume that it relates to the devolution of transport policy or to the separation of legislation that it replaces, but separate-but-fundamentally-identical acts were passed for Scotland and Northern Ireland.

You’ve probably spotted the quirk already. When “special roads” were created, they didn’t have a speed limit. Some “special roads” were categorised as “motorways”, and “motorways” later had a speed limit imposed. But there are still a few non-motorway “special roads”!

Putting a national speed limit sign on a special road would be meaningless, because these roads have no centrally-legislated speed limit. So they need a speed limit sign, even if that sign, confusingly, might specify a speed limit that matches what you’d have expected on such a road4. That’s the (usual) reason why you sometimes see these surprising signs.

As to why this kind of road are much more-common in Scotland and Wales than they are anywhere else in the UK: that’s a much deeper-dive that I’ll leave as an exercise for the reader.

Footnotes

1 The Preston By-pass lives on, broadly speaking, as the M6 junctions 29 through 32.

2 There’s little to stop a local authority using the powers of the Special Roads Act and its successors to declare a special road accessible to some strange and exotic permutation of vehicle classes if they really wanted: e.g. a road could be designated for cyclists and horses but forbidden to motor vehicles and pedestrians, for example! (I’m moderately confident this has never happened.)

3 There’s a statutory instrument that makes those Mancunian sliproads possible, if you’re having trouble getting to sleep on a night and need some incredibly dry reading.

4 An interesting side-effect of these roads might be that speed restrictions based on the class of your vehicle and the type of road, e.g. 60mph for lorries on motorways, might not be enforceable on special roads. If you wanna try driving your lorry at 70mph on a motorway-like special road with “70” signs, though, you should do your own research first; don’t rely on some idiot from the Internet. I Am Not A Lawyer etc. etc.

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ARCC

In the late ’70s, a shadowy group of British technologists concluded that nuclear war was inevitable and secretly started work on a cutting-edge system designed to help rebuild society. And thanks to Matt Round-and-friends at vole.wtf (who I might have mentioned before), the system they created – ARCC – can now be emulated in your browser.

3D rendering of an ARCC system, by HappyToast.

I’ve been playing with it on-and-off all year, and I’ve (finally) managed to finish exploring pretty-much everything the platform currently has to offer, which makes it pretty damn good value for money for the £6.52 I paid for my ticket (the price started at £2.56 and increases by 2p for every ticket sold). But you can get it cheaper than I did if you score 25+ on one of the emulated games.

ARCC system showing a high score table for M1, with DAN50 (score 13012) at the top.
It gives me more pride than it ought to that I hold the high score for a mostly-unheard-of game for an almost-as-unheard-of computer system.

Most of what I just told you is true. Everything… except the premise. There never was a secretive cabal of engineers who made this whackballs computer system. What vole.wtf emulates is an imaginary system, and playing with that system is like stepping into a bizarre alternate timeline or a weird world. Over several separate days of visits you’ll explore more and more of a beautifully-realised fiction that draws from retrocomputing, Cold War fearmongering, early multi-user networks with dumb terminal interfaces, and aesthetics that straddle the tripoint between VHS, Teletext, and BBS systems. Oh yeah, and it’s also a lot like being in a cult.

Needless to say, therefore, it presses all the right buttons for me.

ARCC terminal in which an email is being written to DAN50.
If you make it onto ARCC – or are already there! – drop me a message. My handle is DAN50.

If you enjoy any of those things, maybe you’d like this too. I can’t begin to explain the amount of work that’s gone into it. If you’re looking for anything more-specific in a recommendation, suffice to say: this is a piece of art worth seeing.

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Somewhat-Effective Spam Filters

I’ve tried a variety of unusual strategies to combat email spam over the years.

Here are some of them (each rated in terms the geekiness of its implementation and its efficacy), in case you’d like to try any yourself. They’re all still in use in some form or another:

Spam filters

Geekiness: 1/10
Efficacy: 5/10

A colander filters spam email out of a stream of emails.

Your email provider or your email software probably provides some spam filters, and they’re probably pretty good. I use Proton‘s and, when I’m at my desk, Thunderbird‘s. Double-bagging your spam filter only slightly reduces the amount of spam that gets through, but increases your false-positive rate and some non-spam gets mis-filed.

A particular problem is people who email me for help after changing their name on FreeDeedPoll.org.uk, probably because they’re not only “new” unsolicited contacts to me but because by definition many of them have strange and unusual names (which is why they’re emailing me for help in the first place).

Frankly, spam filters are probably enough for many people. Spam filtering is in general much better today than it was a decade or two ago. But skim the other suggestions in case they’re of interest to you.

Unique email addresses

Geekiness: 3/10
Efficacy: 8/10

If you give a different email address to every service you deal with, then if one of them misuses it (starts spamming you, sells your data, gets hacked, whatever), you can just block that one address. All the addresses come to the same inbox, for your convenience. Using a catch-all means that you can come up with addresses on-the-fly: you can even fill a paper form with a unique email address associated with the company whose form it is.

On many email providers, including the ever-popular GMail, you can do this using plus-sign notation. But if you want to take your unique addresses to the next level and you have your own domain name (which you should), then you can simply redirect all email addresses on that domain to the same inbox. If Bob’s Building Supplies wants your email address, give them bobs@yourname.com, which works even if Bob’s website erroneously doesn’t accept email addresses with plus signs in them.

This method actually works for catching people misusing your details. On one occasion, I helped a band identify that their mailing list had been hacked. On another, I caught a dodgy entrepreneur who used the email address I gave to one of his businesses without my consent to send marketing information of a different one of his businesses. As a bonus, you can set up your filtering/tagging/whatever based on the incoming address, rather than the sender, for the most accurate finding, prioritisation, and blocking.

Emails to multiple email addresses reach the same inbox. Spam emails are blocked based on the addresses they're sent to.

Also, it makes it easy to have multiple accounts with any of those services that try to use the uniqueness of email addresses to prevent you from doing so. That’s great if, like me, you want to be in each of three different Facebook groups but don’t want to give Facebook any information (not even that you exist at the intersection of those groups).

Signed unique email addresses

Geekiness: 10/10
Efficacy: 2/10

Unique email addresses introduce two new issues: (1) if an attacker discovers that your Dreamwidth account has the email address dreamwidth@yourname.com, they can probably guess your LinkedIn email, and (2) attackers will shotgun “likely” addresses at your domain anyway, e.g. admin@yourname.com, management@yourname.com, etc., which can mean that when something gets through you get a dozen copies of it before your spam filter sits up and takes notice.

What if you could assign unique email addresses to companies but append a signature to each that verified that it was legitimate? I came up with a way to do this and implemented it as a spam filter, and made a mobile-friendly webapp to help generate the necessary signatures. Here’s what it looked like:

  1. The domain directs all emails at that domain to the same inbox.
  2. If the email address is on a pre-established list of valid addresses, that’s fine.
  3. Otherwise, the email address must match the form of:
    • A string (the company name), followed by
    • A hyphen, followed by
    • A hash generated using the mechanism described below, then
    • The @-sign and domain name as usual

The hashing algorithm is as follows: concatenate a secret password that only you know with a colon then the “company name” string, run it through SHA1, and truncate to the first eight characters. So if my password were swordfish1 and I were generating a password for Facebook, I’d go:

  1. SHA1 ( swordfish1 : facebook) [ 0 ... 8 ] = 977046ce
  2. Therefore, the email address is facebook-977046ce@myname.com
  3. If any character of that email address is modified, it becomes invalid, preventing an attacker from deriving your other email addresses from a single point (and making it hard to derive them given multiple points)

I implemented the code, but it soon became apparent that this was overkill and I was targeting the wrong behaviours. It was a fun exercise, but ultimately pointless. This is the one method on this page that I don’t still use.

Honeypots

Geekiness: 8/10
Efficacy: ?/10

Emails to multiple email addresses reach an inbox, but senders who reach a "honeypot" inbox are blocked from reaching the real inbox.

A honeypot is a “trap” email address. Anybody who emails it get aggressively marked as a spammer to help ensure that any other messages they send – even to valid email addresses – also get marked as spam.

I litter honeypots all over the place (you might find hidden email addresses on my web pages, along with text telling humans not to use them), but my biggest source of honeypots is formerly-valid unique addresses, or “guessed” catch-all addresses, which already attract spam or are otherwise compromised!

I couldn’t tell you how effective it is without looking at my spam filter’s logs, and since the most-effective of my filters is now outsourced to Proton, I don’t have easy access to that. But it certainly feels very satisfying on the occasions that I get to add a new address to the honeypot list.

Instant throwaways

Geekiness: 5/10
Efficacy: 6/10

OpenTrashmail is an excellent throwaway email server that you can deploy in seconds with Docker, point some MX records at, and be all set! A throwaway email server gives you an infinite number of unique email addresses, like other solutions described above, but with the benefit that you never have to see what gets sent to them.

Emails are delivered to an inbox and to a trash can, depending on the address they're sent to. The inbox subscribes to the trash can using RSS.

If you offer me a coupon in exchange for my email address, it’s a throwaway email address I’ll give you. I’ll make one up on the spot with one of my (several) trashmail domains at the end of it, like justgivemethedamncoupon@danstrashmailserver.com. I can just type that email address into OpenTrashmail to see what you sent me, but then I’ll never check it again so you can spam it to your heart’s content.

As a bonus, OpenTrashmail provides RSS feeds of inboxes, so I can subscribe to any email-based service using my feed reader, and then unsubscribe just as easily (without even having to tell the owner).

Summary

With the exception of whatever filters your provider or software comes with, most of these options aren’t suitable for regular folks. But you’re only a domain name (assuming you don’t have one already) away from being able to give unique email addresses to everybody you deal with, and that’s genuinely a game-changer all by itself and well worth considering, in my opinion.

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Woke Kids

The other weekend, I joined in with the parade at Witney Pride, accompanied by our 10-year-old who’d expressed an interest in coming too.

It was her first Pride but she clearly got the idea, turning up with a wonderful hand-coloured poster she’d made which, in rainbow colours, encouraged the reader to “be kind”.

A Pride parade marches down a high street: Dan and his eldest can be seen in the very background.
You’ve seen pictures of Pride parades before, possibly even ones with me in them.

You know what: our eldest is so woke it makes me embarrassed on behalf of my past self at her age. Or even at twice her age, when I still didn’t have the level of social and societal awareness and care about queer issues that she does already.

A tweeny girl and a 40-something man with rainbows painted on their faces wave flags in a Pride parade. The child has coloured-in a poster saying "be kind".
I’d equipped her with a whistle (on a rainbow lanyard) and instructions that in the event of protests from religious nuts she shouldn’t engage with them (because that’s what they want) but instead just to help ensure that our parade was louder than them! I needn’t have worried though: Witney ain’t Oxford or London and our march seemed to see nothing but joy and support from the folks we passed.

When we got to the parade’s destination, the kid found a stall selling a variety of badges, and selected for herself a “she/her/hers” pronoun pin.

“It’s not like anybody’s likely to look at me and assume that my pronouns are anything other than that,” she explained, “But I want it to be normal to talk about, and I want to show solidarity for genderqueer people.”

That’s a level of allyship that it took me until I was much, much older to attain. So proud!

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Framing Device

Doors

As our house rennovations/attic conversions come to a close, I found myself up in what will soon become my en suite, fitting a mirror, towel rail, and other accessories.

Wanting to minimise how much my power tool usage disturbed the rest of the house, I went to close the door separating my new bedroom from my rest of my house, only to find that it didn’t properly fit its frame and instead jammed part-way-closed.

“Oh,” I said, as the door clearly failed to shut, “Damn.”

Somehow we’d never tested that this door closed properly before we paid the final instalment to the fitters. And while I’m sure they’d have come back to repair the problem if I asked, I figured that it’d be faster and more-satisfying to fix it for myself.

Homes

As a result of an extension – constructed long before we moved in – the house in Preston in which spent much of my childhood had not just a front and a back door but what we called the “side door”, which connected the kitchen to the driveway.

Unfortunately the door that was installed as the “side door” was really designed for interior use and it suffered for every winter it faced the biting wet North wind.

A partially-pebbledashed house.
The side door isn’t visible in this picture: it’s concealed behind the corner of the house, to the left of the car.

My father’s DIY skills could be rated as somewhere between mediocre and catastrophic, but his desire to not spend money “frivolously” was strong, and so he never repaired nor replaced the troublesome door. Over the course of each year the wood would invariably absorb more and more water and swell until it became stiff and hard to open and close.

The solution: every time my grandfather would visit us, each Christmas, my dad would have his dad take down the door, plane an eighth of an inch or so off the bottom, and re-hang it.

Sometimes, as a child, I’d help him do so.

A grey-haired white man wearing spectacles and a boiler suit leans comfortably on a railing alongside industrial machinery.
My paternal grandfather was a practical and hand-on engineer and a reasonable carpenter.

Planes

The first thing to do when repairing a badly-fitting door is work out exactly where it’s sticking. I borrowed a wax crayon from the kids’ art supplies, coloured the edge of the door, and opened and closed it a few times (as far as possible) to spot where the marks had smudged.

Fortunately my new bedroom door was only sticking along the top edge, so I could get by without unmounting it so long as I could brace it in place. I lugged a heavy fence post rammer from the garage and used it to brace the door in place, then climbed a stepladder to comfortably reach the top.

A small box plane perched atop a sloping door.
I figured I’d only need to remove a few millimetres, so I didn’t mind doing it from atop a stepladder. Hey: here’s a fun thing – when I think about planing a door with my grandfather, I think in inches; when I think about doing it myself, I think in metric!

Loss

After my paternal grandfather died, there was nobody left who would attend to the side door of our house. Each year, it became a little stiffer, until one day it wouldn’t open at all.

Surely this would be the point at which he’d pry open his wallet and pay for it to be replaced?

A middle-aged man carrying walking poles on an urban riverbank drags a car tyre that's chained to his waist.
I’m not sure there’s a more apt metaphor for my dad’s ability to be stubborn than this photo of him dragging a tyre around Gateshead as a training activity for an Arctic expedition.

Nope. Instead, he inexpertly screwed a skirting board to it and declared that it was now no-longer a door, but a wall.

I suppose from a functionalist perspective he was correct, but it still takes a special level of boldness to simply say “That door? It’s a wall now.”

Sand

Of all the important tasks a carpenter (or in this case, DIY-er) must undertake, hand sanding must surely be the least-satisfying.

Dan rubs sandpaper atop a wooden door.
You wear your fingers out rubbing a piece of wood smooth, and your only reward is getting to do it again with a slightly finer grade of paper.

But reaching the end of the process, the feel of a freshly-planed, carefully-sanded piece of wood is fantastic. This surface represented chaos, and now it represents order. Order that you yourself have brought about.

Often, you’ll be the only one to know. When my grandfather would plane and sand the bottom edge of our house’s side door, he’d give it a treatment of oil (in a doomed-to-fail attempt to keep the moisture out) and then hang it again. Nobody can see its underside once it’s hung, and so his handiwork was invisible to anybody who hadn’t spent the last couple of months swearing at the stiffness of the door.

A paintbrush applies white paint to the top of a door.
Swish, swish. Now I’m glad I sanded.

Even though the top of my door is visible – particularly visible, given its sloping face – nobody sees the result of the sanding because it’s hidden beneath a layer of paint.

A few brush strokes provide the final touch to a spot of DIY… that in provided a framing device for me to share a moment of nostalgia with you.

Sweep away the wood shavings. Keep the memories.

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