Farnham gave a performance that excelled in parts and disappointed greatly in others.
The home team were not keen to take to the pitch due to the layer of seeming permafrost about two inches below the sandy mud.
Farnham were thus in good psychological order before the kick-off and, with early territorial advantage, scored two quick tries from fine lineout work in the right corner.
First, Gavin Baker collected the ball and, on his return to earth, was shunted powerfully by the pack 10 yards to the line. Karl Baker, captain for the day, emerged grinning, so one can assume that he was claiming the try.
From another driving maul, the ball was spun wide to Matt Payne and then to Rupert Mitchell who swan-dived the last five yards across the line. Farnham thus led 10-0 after just 10 minutes.
But Cranleigh had a spirited response. Cotterill kicked a neat drop goal and Osborne scored their first try before Farnham extended their lead again with a Rooney penalty.
Farnham's forwards then got up another head of steam from a lineout and Adam Christie charged through four defenders (backs though) to score to the right of the posts (18-8).
Before half-time, Rees scored a good try on the right for Cranleigh and a penalty by Futter saw them draw ever closer at 18-16 come the interval.
The second half was a less than pleasant affair. The game became scrappy and there were some strange decisions in favour of both sides.
Cranleigh scored the try of the game when Farnham were down to 13 men (Andrew Mortimore and Payne both sin-binned). Outside-half Cotterill kicked a high ball into Farnham's 22 and Rees collected in mid-air and ran through to score.
Osborne scored his second try after a fine team move and Futter added a superb touchline conversion.
Farnham, now 31-18 down, responded too late and squandered several scoring chances before being awarded a penalty try with only a minute to spare.
It was Cranleigh's fifth league win in six matches. Farnham, who entertain US Portsmouth this Saturday, need a win to consolidate their place in the top four.
Farnham: Cranstone, Christie, Mortimore, Debenham, Baker, Falkiner, Brown, Oakley (Holwill), Edward, Rooney, Mitchell (Southwood), Payne, Doran, Heath, Lewis.
London 4SW
P W D L F A Pts
Richmond 11 11 0 0 598 73 22
Tottonians 13 11 0 2 509 227 22
Barnes 12 10 0 2 487 205 20
Farnham 12 8 0 4 301 259 16
Purley JF 12 6 0 6 212 303 12
Emanuel 11 5 1 5 251 219 11
Cranleigh 12 5 0 7 165 354 10
Trojans 12 4 1 7 218 333 9
Reedonians 13 4 0 9 181 413 8
*US Ports 13 4 0 9 195 329 6
Farnbro 11 2 0 9 161 323 4
*Warlingham 12 1 0 11 122 363 0
* Pts deducted