The church was laid out and begun, and during the whole generation of the workmen that began it, the building was prosecuted with all the means and money that could be procured; and when that generation passed away, the next continued the work, until, at length, in about a hundred years it was so far advanced that a portion of it could have a roof put over it, and be consecrated as a church. They still went on, for one or two centuries more, until they had carried up the walls to a considerable height in many parts, and had raised one of the towers to an elevation of about a hundred and fifty feet. When the work had advanced thus far the government of Holland, in the course of some of the wars in which they were engaged, closed the mouth of the Rhine, so that the ships of Cologne could no more go up and down to get out to sea. This they could easily do, for the country of Holland is situated at the mouth of the Rhine, and the Dutch government was at that time extremely powerful. They had strong fleets and great fortresses at the mouth of the river, and thus they could easily control the navigation of it. Thus the merchants of Cologne could no more import goods from foreign lands for other people to come there and buy, but the inhabitants were obliged to send to Holland to purchase what they required for themselves. The town, therefore, declined greatly in wealth and prosperity, and no more money could be raised for carrying on the work of the cathedral. At the time when the work was interrupted the builders were engaged chiefly on one of the towers, which they had carried up about one hundred and fifty feet. The stones which were used for this tower were very large, and in order to hoist them up the workmen used a monstrous crane, which was reared on the summit of it. This crane was made of timbers rising obliquely from a revolving platform in the centre, and meeting in a point which projected beyond the wall in such a manner that a chain from the end of it, hanging freely, would descend to the ground. The stones which were to go up were then fastened to this chain, and hoisted up by machinery. When they were raised high enough, that is, just above the edge of the wall, the whole crane was turned round upon its platform, in such a manner as to bring the stone in over the wall; and then it was let down into the place which had been prepared to receive it.