NATURAL PHILOSOPHY. 157 



and value to be attached to the subject. If the voyage across the At- 

 lantic can be shortened but a day or two, commerce will still reap im- 

 portant benefits. 



A still further examination of the materials at his command, has 

 led Lieut. Maury to other promising results. By projecting the courses 

 of large numbers of vessels engaged in the trade of the Gulf of Mexico 

 and noting the currents they have met with, it has been made to appear 

 more than probable that a current has been discovered, which (if found 

 to exist) will shorten the usual sailing distance from Havana to New 

 Orleans, and to other ports in the States bordering on the Gulf, nearly 

 one third. By the route usually pursued, vessels have to encounter an 

 opposing current, running at the rate of nearly sixty miles per day. It 

 is believed that, by following along the Cuba shore, vessels bound to 

 New Orleans will find a current in their favour of equal velocity. 



In a letter to some citizens of New Bedford, Lieut. Maury enumerates 

 some of his other results. He says that he has ascertained that " the 

 northeast trade-winds form an atmospherical band in the North Atlantic, 

 with surprising regularity of breadth. Were this band opaque, or were 

 it visible to an astronomer in the moon, it would appear to him not un- 

 like the belts of Jupiter do to us, but upon a scale greatly enlarged. 

 Could it be seen by an observer in the moon, he could mark our seasons 

 by it ; so regularly do the materials already furnished show its vibrations 

 up and down in latitude to be according to our months and seasons. 

 This band of northeast trades is not, as has been supposed, parallel to 

 the equator. It is parallel to the ecliptic. The manner in which these 

 conclusions are arrived at admits of no more doubt as to these facts, 

 than there is as to the existence of the trade-winds themselves." 



Referring to the merchant-vessels, which have been supplied with 

 his charts, he adds, "When these thousand ships return with their 

 observations made simultaneously in all parts of the world, W 7 ho can 

 anticipate the value or the nature of the results to be obtained? 

 When it is blowing a norther in the Gulf, or a tornado in the West 

 Indies, for instance, these observations will enable us to see what it 

 was doing on the other side, across the Isthmus of Tehuantepec. I am 

 beginning to receive returns from this fleet. Our system of observa- 

 tions requires the water-thermometer to be used ; and in consequence 

 it is now beginning, for the first time, to be generally used in the mer- 

 chant service. From the returns already received, this instrument 

 indicates a fork in the Gulf Stream, on the banks of Newfoundland. 

 It also indicates the existence of a cold current setting westwardly 

 between two warm ones running towards the east ; and it indicates, 

 further, the probability of the Grand Banks extending nearly to the 

 coast of Europe. This is all the thermometer can do in this respect ; 

 it can only indicate. Suppose and the supposition is probably not 

 far wrong that the rate of this cold current and of each of these 

 warm ones is one mile the horn- ; vessels do not know where the di- 

 viding line between them is. They lie in the track to Europe ; and if 

 we suppose the average time for which a vessel, on her passage to and 

 fro, is exposed to them to be ten days, we shall see that each vessel 



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