▁ran ▁from ▁Sweden , ▁and ▁the ▁United ▁States ▁cable ▁from ▁the ▁United ▁States ▁emb ass y ▁in ▁Den mark . ▁However , ▁neither ▁cable ▁ran ▁directly ▁to ▁the ▁United ▁States . ▁Both ▁c ables ▁passed ▁through ▁a ▁relay ▁station ▁at ▁P orth c urn o , ▁near ▁Land ' s ▁End , ▁the ▁western most ▁tip ▁of ▁England . ▁Here ▁the ▁signals ▁were ▁boost ed ▁for ▁the ▁long ▁trans - o cean ic ▁jump . ▁All ▁traffic ▁through ▁the ▁P orth c urn o ▁relay ▁was ▁copied ▁to ▁British ▁intelligence , ▁particularly ▁to ▁the ▁ ▁code break ers ▁and ▁anal yst s ▁in ▁Room ▁ 4 0 ▁at ▁the ▁Admir alty . ▁ ▁After ▁their ▁te legraph ▁c ables ▁had ▁been ▁cut , ▁the ▁German ▁Foreign ▁Office ▁appe aled ▁to ▁the ▁United ▁States ▁for ▁use ▁of ▁their ▁cable ▁for ▁diplom atic ▁messages . ▁President ▁Wilson ▁agreed ▁in ▁the ▁belief ▁both ▁that ▁such ▁co - operation ▁would ▁sust ain ▁continued ▁good ▁relations ▁with ▁Germany ▁and ▁that ▁more ▁efficient ▁German - American ▁diplom acy ▁could ▁assist ▁Wilson ' s ▁goal ▁of ▁a ▁negoti ated ▁end ▁to ▁the ▁war . ▁The ▁Germ ans ▁handed ▁in ▁messages ▁to ▁the ▁United ▁States ▁emb ass y ▁in ▁Berlin , ▁which ▁were ▁relay ed ▁to ▁the ▁emb ass y ▁in ▁Den mark ▁and ▁then ▁to ▁the ▁United ▁States ▁by ▁American ▁te legraph ▁operators . ▁However , ▁the ▁United ▁States ▁placed ▁conditions ▁on ▁German ▁usage , ▁most ▁not ably ▁that ▁all ▁messages ▁had ▁to ▁be ▁in ▁clear , ▁or ▁un coded