STORMS. 327 



rate at wlilcli the vessel may be moving througli the water, and 

 the angle which her course makes with the true direction of the 

 wind. Bearing this explanation in mind, the intelligent navigator 

 will have no difficulty in understanding the wind diagram (Plate 

 v.), and in forming a correct opinion as to the degree of credit due 

 to the fidelity with which the prevailing winds of the year are rep- 

 resented on Plate VIII. 



931. As the compiler wades through log-book after log-book, 

 and scores down in column after column, and upon line after line, 

 mark upon mark, he at last finds that, imder the month and from 

 the course upon which he is about to make an entry, he has al- 

 ready made four marks or scores, thus ( H 1 1 ). The one that he 

 has now to enter will make the fifth, and he "scores and tallies," 

 and so on until all the abstracts relating to that part of the ocean 

 upon which he is at work have been gone over, and his materials 

 exhausted. These "fives and tallies" are exhibited on Plate V. 



932. Now, with this explanation, it wiU be seen that in the 

 district marked A (Plate V.) there have been examined the logs of 

 vessels that, giving the direction of the wind for every eight hours, 

 have altogether spent days enough to enable me to record the calms 

 and the prevailing direction of the winds for eight hours, 2144 

 times : of these, 285 were for the month of September ; and of 

 these 285 observations for September, the wind is reported as pre- 

 vailing for as much as eight hours at a time: from N., 3 times ; 

 fromN.N.E., 1; N.E., 2; E.KE., 1; E.,0; E.S.E., 1; S.E.,4; 

 S.S.E., 2; S., 25; S.S.W., 45; S.W., 93 ; W.S.W., 24; W., 

 47; W.N.W., 17; KW., 15; N.N.W., 1; Calms (the little O's), 

 5 ; total, 285 for this month in this district. 



The number expressed in figures denotes the whole number of 

 observations of calms and winds together that are recorded for 

 each month and district. 



934. In C, the wind in May sets one third of the time from 

 west. But in A, which is between the same parallels, the favor- 

 ite quarter for the same month is from S. to vS.W., the wind set- 

 ting one third of the time from that quarter, and only 10 out of 

 221 times from the west ; or, on the average, it blows from the 

 west only 1| day during the month of May. 



