116 



iOIENGE. 



[N. S. Vol. IX. No. 212. 



ing it up is saved mauy times over by the 

 facility witli which reference is made. 



Chaeles S. Ceandall. 

 The State Ageicultueal College, 

 FoET Collins, Coloeado. 



ZONE TEMPEEATUEES. 



My attention has been recently called by Dr. 

 Walter H. Evans, of the United States Depart- 

 ment of Agriculture, to an error in the temper- 

 ature tables accompanying my paper on the 

 ' Laws of Temperature Control of the Geo- 

 graphic Distribution of Animals and Plants, ' an 

 ' abstract of which was printed in my recent 

 bulletin on ' Life Zones and Crop Zones.' The 

 error in question relates to the effective temper- 

 ature or ' sum of normal mean daily tempera- 

 ture above 6°C.' In the tables bearing the 

 a,bove heading the quantities actually given are 

 the sums of normal mean daily temperatures 

 {without deducting the 6°C. each day) for the 

 period during which the mean daily tempera- 

 ture exceeds 6°(^. 



The temperature data, as stated on the first 

 page of my original paper, were furnished by 

 the Weather Bureau. Not being of a mathemat- 

 ical turn of mind, I did not detect the error 

 until my attention was called to it by Dr. 

 Evans. Corrected tables will be given in the 

 next edition of ' Life Zones and Crop Zones.' 

 C. Haet Meeeiam. 



PHYSICAL NOTES. 

 De. Olivee Lodge, in a recent paper before 

 the Institution of Electrical Engineers, speaks 

 of the probable importance of leakage currents 

 in the usual methods of telegraphing by mag- 

 netic inductance through space. This form of 

 wireless telegraphy has usually been accom- 

 plished with long parallel wires on poles and 

 ground returns. In some experiments made 

 by Stephenson near Edinburgh horizontal coils 

 of wire were used and signals transmitted half 

 a mile with a morse key in one coil and a tele- 

 phone receiver in the other. Mr. Lodge used 

 similar coils covering areas of about 4,500 

 square yards and transmitted signals about 

 two miles. The characteristics of his method 

 are the use of an alternating current of a rather 

 high frequency, about 380, and the tuning of 

 the line to this frequency by the use of con- 



densers, that is, the balancing of the inductance 

 so that the current becomes equal to the induced 

 E. M. F. divided by the ohmic resistance. As 

 a result, he gets much greater effects than where 

 the current is principally determined by the 

 inductance of the circuits. This he shows by 

 mathematical determination will be the case, 

 the value of 2- x the frequency, coming in one 

 instance in the denominator, while in the other 

 it comes in the numerator of the expression 

 giving the ratio between the secondary current 

 and the impressed primary E. M. F. 



F. C. C. 



CURRENT NOTES ON METEOROLOGY. 



THE WINDWAED ISLANDS HUEEICANE OF 8EP- 

 TEMBEE, 189S. 



The practical advantages gained by the es- 

 tablishment of the new West Indian Service of 

 our Weather Bureau are forcibly illustrated in 

 the account of the hurricane of September 10th 

 and 11th last, published in the September num- 

 ber of the Monthly Weather Beview. The Weather 

 Bureau Observer at Bridgetown, Barbados, 

 sent a special cable to Washington at 12:40 p. 

 m., September 10th, announcing the approach 

 of a hurricane. Warnings were immediately 

 cabled to Weather Bureau stations in the Lesser 

 Antilles, and the officials in charge were di- 

 rected to give the widest possible distribution 

 to the warnings. Advisory messages were sent 

 to other islands, as far west as Jamaica and 

 eastern Cuba, to points on the South American 

 coast of the Caribbean Sea, and to Admiral 

 Watson's fleet, lying in the harbor of Caimanera, 

 Cuba. The careful reports of the Weather 

 Bureau Observers at Kingston, Jamaica, at 

 St. Kitts and other stations also made possible 

 an early and complete record of the hurricane. 



In this connection another paper, in the same 

 number of the Beview, is of interest. It con- 

 cerns the telegraph service of the Weather 

 Bureau with the West Indies, and is illustrated 

 by a chart showing the routes of the submarine 

 cables over which reports are transmitted and 

 the points at which the cables connect with the 

 land lines. 



At the December meeting of the Royal 

 Meteorological Society (London) Captain A. 

 Carpenter, R. N., gave an account of this dis- 

 asti'ous hurricane. 



