on several occasions room 40 received an unexpected but welcome gift when the German codebook was recovered after a sea battle and presented to the British code breakers. one such gift was a codebook from the German ship Magdebury a light cruiser that ran aground on an island of Finland. when Russian ships quickly bore down on the cruiser the captain of the stranded ship immediately did what any navel officers were taught to do he ordered his signalman to bring him the ships codebook so he could throw the book wrapped in lead covers into the sea. but before signalman could deliver the book to his captain he was killed by Russian guns. when the Russians recovered his body the sailors still was clutching the codebook in his arms. What type of structure is use in the text?