ots ▁the ▁duration ▁of ▁a ▁trans at l antic ▁crossing ▁short ened ▁to ▁around ▁ 7 ▁days , ▁ow ing ▁to ▁the ▁techn ological ▁progress ▁made ▁in ▁the ▁prop ulsion ▁of ▁ships : ▁the ▁rud iment ary ▁steam ▁bo ilers ▁gave ▁rise ▁to ▁more ▁elaborate ▁mach iner ies ▁and ▁the ▁p addle w heel ▁gradually ▁disappeared , ▁replaced ▁first ▁by ▁one ▁hel ix ▁then ▁by ▁two ▁hel ix es . ▁At ▁the ▁beginning ▁of ▁the ▁ 2 0 th ▁century , ▁C un ard ▁Line ' s ▁ ▁and ▁ ▁reached ▁a ▁speed ▁of ▁ 2 7 ▁kn ots . ▁Their ▁records ▁seemed ▁un be atable , ▁and ▁most ▁sh ipping ▁companies ▁abandoned ▁the ▁race ▁for ▁speed ▁in ▁favor ▁of ▁size , ▁lux ury , ▁and ▁safety ▁The ▁advent ▁of ▁ships ▁with ▁dies el ▁engines , ▁and ▁of ▁those ▁whose ▁engines ▁were ▁oil - burn ing , ▁such ▁as ▁the ▁Bre men , ▁in ▁the ▁early ▁ 1 9 3 0 s , ▁rela unch ed ▁the ▁race ▁for ▁the ▁Blue ▁Rib and . ▁The ▁Norm and ie ▁won ▁it ▁in ▁ 1 9 3 5 ▁before ▁being ▁sn atch ed ▁by ▁ ▁in ▁ 1 9 3 8 . ▁It ▁was ▁not ▁until ▁ 1 9 5 2 ▁that ▁ ▁set ▁a ▁record ▁that ▁remains ▁today : ▁ 3 4 . 5 ▁kn ots ▁( 3 ▁days ▁and ▁ 1 2 ▁hours ▁of ▁crossing ▁the ▁Atlantic ). ▁In ▁addition , ▁since ▁ 1 9 3 5 , ▁the ▁Blue ▁Rib and ▁is