I20 



NATURE 



\ytme 13, 1872 



hastily revised. Tlius, in four lines quoted from Ovid, 

 there are two bad misprints, besides a doubtful reading. 



At present the results obtained in this inquiry' are the 

 accumulation of facts and the refutation of untenable 

 explanations. One may also, perhaps, affirm (i) that the 

 primitive condition of man and other vertebrates was, 

 as their early fffital condition still is, one of com- 

 plete bilateral symmetry of structure, and also of func- 

 tional symmetry ; (2) that this primitive ambidextrous 

 use of the limbs is occasionally superseded in animals, 

 and constantly in all races of men of which we have 

 any knowledi^e, by a preferential use of one side ; and 

 that this is a necessary step in development as soon as 

 the more delicate operations performed by a single hand 

 take the place of those of digging, climbing, &c., in which 

 both take part. It is, in fact, a ditferentiation produced 

 by the same causes which have led to the specialisation 

 of the fore and hind limbs in frogs, birds, or kangaroos, 

 compared with their uniformity of structure and function 

 in fishes, crocodiles, and horses ; (3) the prevalent choice 

 of the right hand when differentiation was established, 

 must have depended on some slight advantage, at present 

 unascertained, by which dexterity at last suppressed 

 gaiichcrk; (4) The occasional preference for the left hand, 

 which is often partial and sometimes hereditary, does not 

 depend on any " coarse " structional abnormality, but is 

 an instance of atavism — of reversion to the primitive and 

 universal ambidextrous, or to a subsequent and partial 

 lefthanded condition. P. H. Pye Smith 



LETTERS TO THE EDITOR 



[ The Editor does not hold himself responsible for opinions expressed 

 by his correspondents. No notice is taken of anonymous 

 communications. ] 



Ocean Currents 



If a free body on the earth's surface should be moved from 

 a lower to a higher latitude without friction by a force in the 

 direction of the meridian, it would acquire a certaia amount of 

 relative eastward velocity, which would be the same whether the 

 body moved toward the pole with a very slow uni.fbrm velocity 

 arising from a single imijulse, or whether it moved with a con- 

 tinual accelerated velocity down a gradient by the force of gravity. 

 If a particle of atmosphere or of the ocean is moved in the same 

 way by a similar force, and does not acquire the same amount of 

 relative eastward velocity, the difference between the velocities in 

 the two cases is the true measure of the effect of friction. But 

 from the amount of work done, or velocity generated or de- 

 stroyed, nothing can be inferred with regard to the acting force, 

 unless we take into account the length of time during which it 

 acts. The velocity of the interchanging motion of the water 

 between the equator and the pole, discovered by Dr. Carpenter, 

 is extremely small, perhaps not as much as a mde per day, and 

 less than tidal velocities in the open ocean. If a great amount of 

 eastward velocity, therefore, is destroyed by friction in the case 

 of a particle of the ocean ia moving I'rom a lower to a higher 

 latitude, it is not because the friction is great, but because it acts 

 during a very long time. 



If the velocity m the direction of the meridian were one mile 

 per day, the deflecting force, at the parallel of 45°, arising from 

 the earth's rotation, would be about equal to the force of gravity 

 along a regular gradient of 6ft. between the equator and the pole. 

 Both the velocities north or south and east or west, and the 

 amount of friction belonging to any given velocity, are unknown 

 quantities. The force down the gradient of 6 ft. between the 

 equator and the pole, which Mr. CroU allows to be the measure 

 of the force due to the difi'erence of temperature or density be- 

 tween the equator and the pole, would soon give the particles of 

 water without friction the velocity of one mile per day, and the 

 question now is, whether the force would then be sufficient to 

 overcome the friction belonging to this small velocity ; for the 

 inertia of the water being once overcome, all that would be re- 

 quired of the force would be to overcome the friction. 



The velocity of motion between the equator and the pole being 

 probably of the same order only as tidal velocities, we may sup- 

 pose the friction in the two cases to be somewhat of the same 



order. Now the friction in tidal velocities in the open sea, when 

 not regarded as entirely insensible, has always been regarded as 

 a quantity of a second order in comparison with the disturbing 

 foices producing the tides, or at least as being much less. But 

 the force producing the tides is about e.jual to the furce of 

 gravity along a gradient of two feet between the t<iuator and the 

 jioles. If we therefore suppose the force necessary to overcome 

 the friction of tidal velocities to be one-fourth of that producing 

 the tides, then the force of gravity on a gradient of 6 in. between 

 the equator and the poles, would be sufficient to overcome the 

 frictim belonging to the slow velocities of the motion discovered 

 by Dr. Carpenter, if we suppose, as above, that the amount of 

 friction in the two cases is of the same order. But this is only 

 one-twelfth part of what Mr. Croll allows to be the available 

 force for this purpose. According to the preceding view, there- 

 fore, the difficulty is not in finding a sufficient force for overcoming 

 the friction of Dr. Carpenter's slow velocities, but in disposing of 

 the abundance of force we have on hand for that purpose. 

 Washington, May 24 Wm. Ferrei, 



The Wanderings of the Esquimaux 

 I AM much obliged to Dr. Rae for his courteous letter upon a 

 subject in which he is so deservedly an authority, while I am 

 only a student. The question upon which he joins issue with 

 me, namely, the southerly migration of the Esquimax, is one 

 upon which I ought to bow to his authority ; but there are 

 some difficulties attending the solution he offers which deserve, 

 I think, consideration. If the Greenland Esquimaux came from 

 the north, as both of us are agreed, it is probable that the stock 

 from which they sprung are the so-called Arctic Highlanders of 

 Smith's .Sound, about whom Mr. C. Markham has written both 

 in the Ethnological Journal and the Journal of the Gcoi;raphical 

 Society. They are broadly distinguished from the Esquimaux of 

 America by the use of stone igloos instead of snow huts, and by 

 their ignorance of boats, either kayaks or omenaks. These Arctic 

 Highlanders are a diminishing race. M'Clintock tells us " that 

 they have become alarmed by the rapid diminution of their num- 

 bers through famine and disease" (Travels, 137). Along the 

 shores of Smith's Sound are the ruins of many deserted huts, 

 moss-grown, and of considerable antiquity. The skulls of musk 

 oxen without their lower jaws, a proof that they had been killed 

 by Esquimaux, are also found scattered along the same coast 

 (id. 76). These facts show that the Esquimaux were formerly 

 abundant in very high latitudes, where they have now become 

 very few in number. What is true of Smith's Sound is also 

 true of the great Archipelago of the Arctic circle known as the 

 I'arry Islands. These also are dotted with the moss-grown ruins 

 of ancient and deserted huts, the remains of a once numerous 

 race in an area now, I believe, entirely deserted by die Esqui- 

 maux. These two places are in the highest latitudes yet reached 

 by navigators. 



Dr. Kae would make these Northern Esquimaux to be wan- 

 derers fronv the American Continent; but, putting aside the 

 difference of customs, which seem to show that the American 

 Esquimaux are not the primitive stock of the race, but have 

 been sophisticated by contact with the Indians, I may quote 

 the following passage from Mr. Markham, who has studied the 

 question with some care : — " The American Esquimaux never go 

 from their o.vn hunting range for any distance to the inhospit- 

 able north. Except in the case of the Pond's Bay natives whc^ 

 followed up the whalers for a specific reason, there is no instance 

 of their having gone north, and it is unreasonable to suppose that 

 they would do so " [Journal of Ethnological Society, 4, new series, 



135)- 



When I quoted the traditions about the migration of the 

 Esquimaux having been southerly, I had the passage especially in 

 my mind where Sir John Franklin describes the Chippewyan 

 legend about the discovery of copper, beginning with the words, 

 '■ The Chippewyaus suppose the Esquimaux originally inhabited 

 some land to the northward, which is separated by the sea from 

 this country ; and that in the earliest ages of the world a party 

 of these men came over and stole a woman from their tribe, 

 whom they carried to this distant country, and kept in a state ot 

 slavery, &c." (Franklin's Narrative, 146). 



Dr. Rae, on the contrary, thinks they came from the west. 

 Now Mackenzie, who certainly knew the country well, says : — 

 "The progress of the Esquimaux, who possess the sea-coast from 

 the Atlantic through Hudson's Straits and Bay, round to Mac- 

 kenzie River, and, I believe, further, is inoion to be tvcstward. 

 They never quit the coast " (Mackenzie's Travels, 406). 



