TO THE

READER.

A decorative woodcut initial letter 'V' begins the text, featuring ornate leaf and vine motifs within a square frame.

It is unnecessary to elaborate on the great necessity of nautical charts in seafaring, or how important it is that they be made and charted with the utmost accuracy, as this is sufficiently known to everyone who understands that they serve as guides on an unpaved path.

If the clean charting of accurate observations is the most essential part of nautical charts, then it is surprising that no greater care is taken in this regard, especially regarding waterways where daily experience provides the opportunity to examine everything properly.

Are there any places more visited by our shipping than the North and especially the Oost-zee Baltic Sea? And yet one sees that the majority of maps of those regions differ from one another so much that in many places, which should display the same thing, there is no agreement at all.

When one considers the cause of this discrepancy, one will easily discover that it arises primarily because the observers have not been circumspect or knowledgeable enough regarding the manner in which observations must be conducted.

For almost everything one has regarding the charting of the Oost-zee Baltic Sea has been made by compasses, based on the direction of courses and the distances of the same. Yet because the compass alone is not sufficient (to which is added that during sailing, little attention is often paid to the flow of the currents) as it is subject to many changes due to various causes, it cannot be otherwise than that observations made by various, undistinguished compasses, and the charting made accordingly, when brought together, must appear quite different from the true shape of the lands.

But as if it were not enough to commit errors through observations made in the above-mentioned manner, many have made the maps even worse by laying out the direction of places according to the miswyfing magnetic declination/variation that one claims the compasses have in those places. Yet because experience teaches that when the miswyfing magnetic declination is examined with different compasses, it is often found to be different in one and the same place, and that the miswyfing magnetic declination in one and the same place is not always the same, no matter how accurately the observations are made, it is evident beyond a doubt what is to be judged of a building that is constructed on such a loose foundation.

As far as our charts are concerned, we have tried to our best ability to prevent the errors committed by others, and have laid out the places according to the most accurate observations of the Pools hoogte latitude/pole height; taking to our aid that which we have chosen as the very best from many daily experiences; everything has been charted according to true South and North: such that we hope this labor of ours will gain the approval of the true experts of this science, and that these charts will be judged to be the best that have been made of these regions to date.