This research note explores the specifics of the Sound Toll Registers as a historical source. It accounts for the shipmasters who sailed into the Baltic but are largely absent from the Sound Toll Registers because they were not attributed to a port. A method of detecting these shipmasters is proposed, together with an explanation as to why this administrative practice developed.

中文翻译：

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目的地未知：波罗的海航运地理和 18 世纪的健全收费登记系统

本研究笔记探讨了作为历史来源的声音收费登记册的细节。它解释了航行到波罗的海的船长，但由于他们不属于港口，因此大部分都没有出现在声音收费登记册中。提出了一种检测这些船长的方法，并解释了这种管理实践发展的原因。