It is housed in a Martello A series of such towers, some 12 m (40 ft) high and 2.5 m (8 ft) thick, were constructed along the coast at the beginning of the 19th century to guard against invasion by Napoleon.
( ( It ( is ( housed ( in ( ( a ( Martello ( A series ) ) ) ( of ( such towers ) ) ) ) ) ) ) ( , ( ( ( ( ( ( some ( ( 12 m ) ( ( -LRB- ( ( 40 ft ) -RRB- ) ) high ) ) ) and ) ( 2.5 ( m ( -LRB- ( ( 8 ft ) -RRB- ) ) ) ) ) thick ) , ) ( ( were ( ( constructed ( along ( ( the coast ) ( at ( ( the beginning ) ( of ( the ( 19th century ) ) ) ) ) ) ) ) ( to ( ( guard ( against invasion ) ) ( by Napoleon ) ) ) ) ) . ) ) ) )
(ROOT (S (S (NP (PRP It)) (VP (VBZ is) (VP (VBN housed) (PP (IN in) (NP (NP (DT a) (NNP Martello) (NNP A) (NN series)) (PP (IN of) (NP (JJ such) (NNS towers)))))))) (, ,) (NP (NP (DT some) (ADJP (CD 12) (JJ m)) (PRN (-LRB- -LRB-) (NP (QP (CD 40) (CD ft))) (-RRB- -RRB-)) (NN high)) (CC and) (NP (CD 2.5) (NN m) (PRN (-LRB- -LRB-) (NP (QP (CD 8) (CD ft))) (-RRB- -RRB-))) (ADJP (JJ thick)) (, ,)) (VP (VBD were) (VP (VBN constructed) (PP (IN along) (NP (NP (DT the) (NN coast)) (PP (IN at) (NP (NP (DT the) (NN beginning)) (PP (IN of) (NP (DT the) (JJ 19th) (NN century))))))) (S (VP (TO to) (VP (VB guard) (PP (IN against) (NP (NN invasion))) (PP (IN by) (NP (NNP Napoleon)))))))) (. .)))
A number of these towers, which were built to guard against invasion by Napoleon, were built along the coast in the 19th century.
( ( ( ( ( ( A number ) ( of ( these towers ) ) ) , ) ( which ( were ( built ( to ( ( guard ( against invasion ) ) ( by Napoleon ) ) ) ) ) ) ) , ) ( ( were ( built ( along ( ( the coast ) ( in ( the ( 19th century ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (DT A) (NN number)) (PP (IN of) (NP (DT these) (NNS towers))) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBD were) (VP (VBN built) (S (VP (TO to) (VP (VB guard) (PP (IN against) (NP (NN invasion))) (PP (IN by) (NP (NNP Napoleon)))))))))) (, ,)) (VP (VBD were) (VP (VBN built) (PP (IN along) (NP (NP (DT the) (NN coast)) (PP (IN in) (NP (DT the) (JJ 19th) (NN century))))))) (. .)))