1. Place the cucumbers in a saucepan and cover with the brine.
2. Heat the water almost to boiling point, but do not actually boil. Simmer for 10 minutes.
3. Drain the brine from the pan and let the cucumbers cool.
4. While the cucumbers are cooling place the vinegar and pickling spice in a saucepan. Bring to the boil for a minute and then remove from the heat.
5. You can pack the cucumber into the jar and pour on the vinegar when it has cooled if you prefer or you can pour the vinegar on while still hot and seal straight away using a warm Kilner jar.