As someone has mentioned, it should be like water. That way, it will 'wick' down the hinge material and into the slot far enough.

A handy trick is to drill a hole right in the centre of the hinge slot with a dremel or other high speed tool. Using a high speed tool will give you a nice clean hole. Only has to be a small hole (1/16 or something), but it makes the CA wick right to the back of the slot......you'd be surprised at how little the CA will penetrate sometimes without it.

Also, don't pour gallons of CA in there......2 to 3 drops max per side is generally more than enough (depending on the size of the hinge of course). If you use too much, it will harden outside the hinge slot and can actually cut the hinge in half (eventually). Not good!