"... a matter for you whether possession is proved as against either of the defendants, but you can see it is open to you to say, 'Well, we think that one defendant did know where these items were, did have control of them - in other words, could get at them - but we are not sure about the other one.' You might take a view, on all the evidence in the case, that the two defendants were involved together, and then you can say they are both in possession."