# Difference between revisions of "Cambridge Surprise"

## Preamble

The traditional extension of Cambridge to any (even) number of bells can be simply described as the right-place treble-dodging method with maximal hunting when the treble dodges, maximal dodging when the treble hunts, and no places made in (n-1)ths place over the treble. An alternative long and tedious explanation of how the method works is given below (although since there's no music below the treble at any stage from Royal up... it's difficult to understand why you'd want to know...).

## How to Ring Cambridge on 10,000 Bells

Cambridge is just treble-bob hunting with a few lumps (sets of places) in. You can ring it on ANY NUMBER of bells by watching the treble (which we've all been doing right from the moment we first rang Grandsire Doubles). The idea is you dodge everywhere unless the treble intervenes. What this means is that when you get to the point where you need to dodge, you ("0" in the diagrams) look to see if the treble ("1" in the diagrams) is ADJACENT to you -- if you're hunting up this means it will be striking over you; if you're hunting down, you will be striking over it:

hunting up ...

``` 0......1
.0....1.
0....1..
.0..1...
..0..1..
...01...  <- treble strikes over you in this row so
...10...  <- miss this dodge and strike over treble
..1..0..  <- hunt up to the next dodging position
...1..0.  <- and miss that dodge as well
..1....0
.1....0.
1......0
```

hunting down ...

``` 1......0
.1....0.
..1....0
...1..0.
..1..0..
...10...  <- you strike over treble in this row so
...01...  <- miss this dodge (treble strikes over you)
..0..1..  <- hunt down to the next dodging position
.0..1...  <- and miss that dodge as well
0....1..
.0....1.
0......1
```

In either case you MISS a dodge, pass the treble and MISS THE NEXT DODGE TOO (as you are still adjacent to the treble, and the rule applies on both sides of the treble whichever direction you're going). The lead-and-dodge / dodge-and-lead work also adheres to the general principle of missing one dodge on each side of the treble's path:

hunting up ...

``` 0...1...
.0.1....
0.1.....
0..1....
.01.....  <- treble strikes over you in this row so
.10.....  <- miss this dodge and strike over treble
1..0....  <- hunt up to the next dodging position
.1..0...  <- and miss that dodge as well
1....0..
1...0...
.1...0..
1.......
```

hunting down ...

``` 1.......
.1...0..
1...0...
1....0..
.1..0...
1..0....
.10.....  <- you strike over treble in this row so
.01.....  <- miss this dodge (treble strikes over you)
0..1....  <- hunt down to the next dodging position
0.1.....  <- and miss that dodge as well
.0.1....
0...1...
```

DIGRESSION: the reason we need to do this is that the basic treble bob hunting from which the method is constructed is "out-of-phase" with the treble (i.e. you hunt when it dodges and it hunts when you dodge), so we must miss a dodge to get back in phase so we can pass the treble when BOTH of you are hunting. Missing the second dodge puts us back out of phase again. You don't actually need to know this to RING Cambridge, however.

Meanwhile: if the treble is NOT adjacent to you immediately before a dodge, you do the dodge and look (or listen) again. If the treble is NOW adjacent to you, the dodge that you just did was the first dodge of a set of places. Once again the rule applies on BOTH sides of the treble whichever direction you are hunting in because the places are (skewly) symmetric about the treble's dodge. Always think of the places as "dodge, far place, near place, dodge with the treble, far place, near place, dodge", and remember that all the dodges are in the SAME direction, which is also your "direction of travel".

DIGRESSION: the regular succession of places in Cambridge creates a series of "boxes" in the structure of the treble-bob hunting, with the treble moving from box to box. Each bell that misses a dodge each side of the treble is passing through two sets of places.

``` .1.23...0.  <-  the 2nd and 3rd are both making places "down", with
..12.3.0.4      the 3rd one position (two places) higher than the 2nd
..213.0.4.
..1230.4..  <-  3rd makes a far place and 4th starts places down above it
..21034...
..2013.4..  <- "box" created by the 2nd making a far place and the 3rd
..02314...      making a near place.  You and the treble cross in this box
.0.2134...  <- "box" created by the 2nd making a near place and the 4th
0.2.31.4..      making a far place.  The treble dodges in this box
...23.14..  <- "box" created by the 3rd making a far place and the 4th
making a near place. The treble and another bell cross.
```

Meanwhile: there is however ONE exception to these rules, and that is when you are adjacent to the treble at the back of the row. In this case you do a DOUBLE DODGE rather than places or missing a dodge. The rule still applies BELOW the treble however, so you still need to miss ONE dodge. It goes like this:

```hunting up ...
```
``` 0...1.
.0...1
0....1
.0..1.
..0..1
...01.  <- treble strikes over you in this row so
...10.  <- miss a dodge and strike over treble
..1..0  <- hunt up to the next dodging position
...10.  <- do this dodge (exceptionally)
..1..0  <- hunt up again
.1..0.  <- do a SECOND dodge
1....0  <- and resume treble-bobbing
.....0
```

hunting down ...

``` .....0
1....0
.1..0.
..1..0
...10.  <- strike over treble in this row so
..1..0  <- do a SECOND dodge (exceptionally)
...10.  <- strike over the treble a second time
...01.  <- hunt down (treble strikes over you)
..0..1  <- hunt down to the next dodging position
.0..1.  <- and miss that dodge
0....1
.0....  <- resume treble-bobbing
0.....
```

The awkward bit is the symmetrical work behind with the treble, because the guide is slightly less obvious. The treble is in the adjacent dodging position, but separated from you by one bell:

hunting up ...

``` ..1...0.
...1...0
....1.0.
.....1.0  <- The treble is ONE bell below you (coursing you up)
....1.0.  <- an exceptional second dodge puts you in phase with it
.....1.0
......10
......01
......10
......01
--------  <- axis of symmetry
......01
......10
......01
......10
.....1.0
....1.0.
.....1.0
....1.0.  <- The treble is one bell below you (you're coursing it down)
...1...0  <- an exceptional second dodge puts you out of phase again
..1...0.
```

... and down again

DIGRESSION: this works because we can also get back in phase with the treble by doing an extra dodge as well as by missing one out. If we applied the rule consistently, we would need to make a pair of adjacent places in Nths and (N-1)ths as the treble dodged in (N-2)-(N-3). This would create Cambridge frontwork upside-down on the back and have bells doing "dodge-and-lie" and "lie-and-dodge" as they worked with it. In fact the result would be a rather elegant double method like Bristol or Superlative, but it's not rung because it doesn't have Plain Bob lead-heads. For the record, the 8-bell version has the place-notation -38-14-1258-36-1478-58-16-78 and hasn't been rung to a peal.

AHA! I hear you cry. What about the frontwork? Surely that's an exception too? Well surprisingly it isn't, it's just another set of places. To see this you have to divide up the work correctly. In fact it's only HALF a set of places because we don't make the half above the treble -- the second's place over the treble is a point of top-to-bottom symmetry in the line as a whole, so we turn round and ring the second half of the frontwork, effectively making the SECOND half of a set of places "down". The usefulness of treating the frontwork as a set of places is that if we forget we're actually doing frontwork, we just check the treble after our 1-2 up dodge and we won't go sailing off the front like amateurs.

Well, that was all pretty long-winded, I hope it's some use to someone. The problem with learning Cambridge on 6 is that you don't get enough of the general principle to see what it is. Learning on higher numbers requires a bit more in the rope-sight department, but you see more of the "system", and needn't actually learn the line (though that's useful too). What do you mean you didn't get taught Grandsire Doubles or watching the treble? Demand your money back from your ringing master RIGHT NOW!