Page:Popular Science Monthly Volume 3.djvu/745

Rh him in making this observation exactly. She obeyed his instructions, and, the moment the shadow reached its highest angle and showed the minutest symptom of declension, she said 'Now,' and Hazel called out in a loud voice" (why did he do that?) "'Noon!' 'And forty nine minutes past eight at Sydney,' said Helen, holding out her chronometer; for she had been sharp enough to get it ready of her own accord. Hazel looked at her and at the watch with amazement and incredulity. 'What?' said he. 'Impossible! You can't have kept Sydney time all this while.' 'And pray why not?' said Helen. 'Have you forgotten that some one praised me for keeping Sydney time? it helped you somehow or other to know where we were.'" After some discussion, in which she shows how natural it was that she should have wound up her watch every night, even when "neither of them expected to see the morning," she asks to be praised. "'Praised!' cried Hazel, excitedly, 'worshipped, you mean. Why, we have got the longitude by means of your chronometer. It is wonderful! It is providential. It is the finger of Heaven. Pen and ink, and let me work it out.'" He was "soon busy calculating the longitude of Godsend Island." What follows is even more curiously erroneous. "'There,' said he. 'Now, the latitude I must guess at by certain combinations. In the first place the slight variation in the length of the days. Then I must try and make a rough calculation of the sun's parallax.'" (It would have been equally to the purpose to have calculated how many cows' tails would reach to the moon.) "'And then my botany will help me a little; spices furnish a clew; there are one or two that will not grow outside the tropic,'" and so on. He finally sets the latitude between the 26th and 33d parallels, a range of nearly 500 miles. The longitude, however, which is much more closely assigned, is wrong altogether, being set at 103½° west, as the rest of the story requires. For Godsend Island is within not many days' sail of Valparaiso. The mistake has probably arisen from setting Sydney in west longitude instead of east longitude, 151° 14'; for the difference of time, 3h. 11m., corresponds within a minute to the difference of longitude between 151° 14' west and 103½° west.

Mere mistakes of calculation, however, matter little in such cases. They do not affect the interest of a story even in such extreme cases as in "Ivanhoe," where a full century is dropped in such sort that one of Richard I.'s knights holds converse with a contemporary of the Conqueror, who, if my memory deceives me not, was Cœur de Lion's great-great-grandfather. It is a pity, however, that a novelist or indeed any writer should attempt to sketch scientific methods with which he is not familiar. No discredit can attach to any person, not an astronomer, who does not understand the astronomical processes for determining latitude and longitude, any more than to one who, not being a lawyer, is unfamiliar with the rules of conveyancing. But, when an attempt is made by a writer of fiction to give