CORRESP ONDENCE. 



411 



demic. If through your published articles 

 intelligent observation is directed toward 

 the dangers inherent in our insect pests, 

 and means are discovered to avert them, 

 you will deserve the undying gratitude of 

 suffering humanity. 



Respectfully, A. G. Boardman. 

 Macon, Geobgia, September 22, 1883. 



TIDAL ANOMALIES. 



Messrs. Editors : 



Professor R. W. McFarland (" Pooular 

 Science Monthly," volume xii, page 106), 

 after demonstrating, as a result of Professor 

 Schneider's theory, a great inequality in the 

 daily range of the tides, confidently asks, 

 " Do your New York tides play such tricks ? " 



However it may be with the New York 

 tides I will not undertake to say, but there 

 are numerous localities upon the globe where 

 the tides do play such or at least similar 

 " tricks," seemingly at variance with estab- 

 lished theories, and in some places these 

 "tricks" appear to be contrary to all our 

 preconceived notions of hydrodynamics. 

 Thus, at the entrances of the various United 

 States ports in the Gulf of Mexico, the tides 

 either exhibit a great inequality in their 

 daily range, or but one flood and ebb tide 

 occurs in the course of the twenty-five hours 

 usually occupied by the two tides. The one- 

 tide phenomenon is again met with among 

 the Philippine Islands; while tides exhib- 

 iting considerable daily inequality in their 

 range are met with in numerous other places. 



That part of the St. George's Channel 

 called the Irish Sea included between the 

 fifty-third and fifty-fifth parallel of latitude 

 contains a body of water covering an area of 

 about ten thousand square miles, inclosed 

 on all sides, except at the two entrances, 

 north and south of Ireland. Throughout 

 this entire body of water the time of high 

 water is nearly simultaneous, the difference 

 nowhere exceeding an hour. Here the aver- 

 age mean range of the tides is not less, prob- 

 ably, than twenty feet. The water to sup- 

 ply and exhaust this broad area of unusually 

 large range of tides has to pass in and out 

 at the two entrances simultaneously with 

 the rise and fall of the water in the Irish Sea. 



Now, the puzzling thing about these tides 

 i3, owing to the time of high water at the 

 two entrances being about five hours earlier 

 than in the Irish Sea, at least two thirds of 

 all this water passing in and out of the St. 

 George's Channel has the appearance of 

 running from a lower to a higher level. 

 Here the tides exhibit another curious freak 

 in the distribution of their range. On the 

 east coast of Ireland, between Wexford and 

 Wicklow Head, for some distance there are 

 no rise and fall to the tides ; while directly 

 on the opposite side of the channel, on the 

 coast of Wales, the mean range is not less 

 than fifteen feet. 



But this anomaly of the water appar- 

 ently running up-hill, as exhibited by the 

 tides, will be found more clearly marked at 

 the Strait of Gibraltar, where the motion of 

 the tidal wave is easterly, and the easterly 

 tidal stream begins at high water, and the 

 westerly tidal stream begins at low water. 

 The same phenomenon is met with again 

 at the Strait of San Bernardino, Philippine 

 Islands, and also on our own coast, in Mar- 

 tha's Vineyard Sound, where the motion of 

 the tidal wave is westerly, and the westerly 

 tidal stream begins at high water. At Cook's 

 Strait, New Zealand, the motion of the tidal 

 wave is westerly, and the westerly stream 

 begins at half flood. 



These are only a few of the more clearly 

 marked of the many anomalies that have 

 come under my observation while endeav- 

 oring, as a navigator, to make myself ac- 

 quainted with the concrete phenomena of 

 the tides. 



In the absence of a better explanation 

 of these anomalies, I offer the following hy- 

 pothesis : That the established theory of the 

 tides is substantially correct ; but, that the 

 primary tidal tcave is in the liquid portion of 

 the earth beneath the solid {though to a greater 

 or less extent flexible) crust ; and that the 

 tidal phenomenon as it reveals itself to us is 

 a secondary tidal, undxdalory motion, deriv- 

 ing its impulse from, and is complicated by, 

 the variable flexibility of the solid crust be- 

 tween the two liquid portions of the earth. 



George W. Grim (Bark Coryphene). 

 Yokohama, Japan. 



ELEPHANTS' TEICKS. 

 Messrs. Editors: 



The following extract from an old edi- 

 tion of the " Arabian Nights " (Edinburgh, 

 1772), may be of interest, showing as it 

 does that at an early date elephants were 

 trained to perform tricks which excite the 

 curiosity if not the wonder of the spectators 

 in the modern shows. It is from the story of 

 " Prince Ahmed and the Fairy Pari-Banou " : 



" But what the Prince Houssain most of 

 all admired was the ingenious address and 

 invention of some Indians, to make a large 

 elephant stand with his four feet on a post 

 which was fixed into the earth, and stood 

 out of it above two feet, and beat time with 

 his trunk to the music. Beside this there 

 was another elephant as big as this and no 

 less surprising; which being set upon a 

 board which was laid across a strong rail 

 about ten feet high, with a great weight at 

 the other end which balanced him, kept time 

 by the motions of his body and trunk as 

 well as the other elephant, and both in the 

 presence of the king and his whole court." 



When this story was written I do not 

 know, as this edition gives no notes as to 

 the original sources of the stories. 



Respectfully, Davis L. James. 

 Cincinnati, October 6, 1833. 



