The bastions are named after the first person to land in the attack of 1704, Captain Sir William Jumper RN. North jumpers was built on the site of a Spanish Santa Cruz Bastion. In 1841 General John Jones recommended that both bastions be rebuilt.
Jumpers or North Jumpers Bastion
On the recommendations of General Jones this was expanded to a demi-bastion with six guns in casemates on the South Flank. The six casemates had accommodation for 32 men each. The other two sides of the demi bastion were designed primarily for defence with small arms. There were gun embrasures on the ramparts and in 1859 the battery mounted six 32-pdr of 33cwt.
Little Jumpers or South Jumpers Bastion
Also, a product of the General Jones report of 1841 this small bastion primarily provided accommodation with the ramparts and adjacent walls designed for small arms defence.
The armament return 1886 show no guns mounted one either bastion, but it is probable that 24-pdr or 32-pdr guns were in some of the emplacements.