For the purposes of the calculator a solution erring in excess was also required, and this Snell gave by slightly varying the former construction.
Using a desk calculator in 1949, D. F. Ferguson calculated it correctly to more than one thousand digits.
In the midst of this chopping sea of civilized life, such are the clouds and storms and quicksands and thousand-and-one items to be allowed for, that a man has to live, if he would not founder and go to the bottom and not make his port at all, by dead reckoning, and he must be a great calculator indeed who succeeds.
To oversee all the details yourself in person; to be at once pilot and captain, and owner and underwriter; to buy and sell and keep the accounts; to read every letter received, and write or read every letter sent; to superintend the discharge of imports night and day; to be upon many parts of the coast almost at the same time--often the richest freight will be discharged upon a Jersey shore;--to be your own telegraph, unweariedly sweeping the horizon, speaking all passing vessels bound coastwise; to keep up a steady despatch of commodities, for the supply of such a distant and exorbitant market; to keep yourself informed of the state of the markets, prospects of war and peace everywhere, and anticipate the tendencies of trade and civilization--taking advantage of the results of all exploring expeditions, using new passages and all improvements in navigation;--charts to be studied, the position of reefs and new lights and buoys to be ascertained, and ever, and ever, the logarithmic tables to be corrected, for by the error of some calculator the vessel often splits upon a rock that should have reached a friendly pier--there is the untold fate of La Prouse;--universal science to be kept pace with, studying the lives of all great discoverers and navigators, great adventurers and merchants, from Hanno and the Phoenicians down to our day; in fine, account of stock to be taken from time to time, to know how you stand.
As an arithmetical calculator he was not only wonderfully expert, but he seems to have occasionally found a positive delight in working out to an enormous number of places of decimals the result of some irksome calculation.
The rules are curious and interesting, but of very doubtful utility, as the formulae are best remembered by the practical calculator in their unconnected form.