When I began to direct my particular attention to the balance-sheets of the Hamburg Marine Insurance Societies, I hoped that a minute examination would lead to conclusions of general interest, and enable us to judge of the risks and state of navigation in general. I hoped that the collection of data and the comparison of the different balance-sheets would not offer great difficulties, and that my examinations might embrace a long period. My hopes have not been fulfilled. I perceived very soon that the work would be very troublesome, and that it would be difficult to form a complete collection of balance-sheets. There were none at the Public Commercial Library, and it was only by the aid of private friends that I at length succeeded in forming a complete collection of the balance-sheets since 1847. Thus I was obliged to limit my comparisons to the years 1847-53; and I think this is the principal reason why the law which governs the events cannot be deduced, and why no general conclusions can be drawn.