Tower 70 was used in artillery experiments as a practice target during artillery trials in 1876. The Eastbourne Chronicle of October 28, 1876 stated that:
"On Wednesday, pending the arrival of the larger howitzer, it was determined to proceed with another stage and to try the effect of different projectiles for breaching purposes on masses of masonry. To do this, the 64-pounder gun was removed from its old position so as to command one of the dismantled Martello towers. The results furnished satisfactory bases for comparative analysis. The gun was laid to a nicety, and the first shot carried away a huge block of masonry from the top corner; succeeding shots did more or less destruction."
The Eastbourne Gazette of November 1, reported:
"The gunnery experiments on Wednesday were confined to tests of the breaching power of different projectiles fired against solid masonry. The defensive work was represented by the remains of a dismantled martello tower after the twentieth round only a fragment of the thick brick wall was left standing."
The tower had already been undermined by the sea, being abandoned in 1872 along with Tower 69. An unknown local artist captured the progress of the tower's undermining and collapse. The one at left shows the remains of 70 with 69 beginning to crack behind it. West Langney Fort had by this time already succumbed to the sea and been washed away.
The site of the tower is on today's low tide mark.
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| Tower 69 | Tower 71 |