344 



SCIENCE. 



[Vol. V., No. 116: 



A TYPHOON IN SICILY. 



In the early morning of the 7th of October, 1884, 

 Etna was seen to be covered with a mantle of clouds, 

 which spread themselves in a nOrth-west direction. 

 At eight o'clock there was a barometric depression 

 throughout the whole western part of Sicily, the mer- 

 cury falling two millimetres. During the typhoon, 

 which began at about noon, the barometer registered 

 761.1 millimetres, whereas in the morning at nine 

 o'clock ic stood at 761.8 millimetres. The normal 

 average is 762.5 millimetres. The thermometer at 

 nine o'clock was 22.5° C, and during the storm went 

 up slightly. The relative humidity at nine was 0.78, 



thrown through a window 10 metres from the ground, 

 while another pierced a house like a bullet. 



CREEPING OF RAILS. 



It has been observed by those having charge of 

 railroad-tracks, that in some places the rails move 

 longitudinally, or 'creep.' On double-tracked lines 

 the rails tend to move in the direction of the traffic; 

 but on single-tracked roads the alternating direction 

 of the trains will naturally neutralize this tendency. 

 Again: on long inclines or grades the track may 

 creep down hill, — a phenomenon which is 

 reasonably attributed to expansion and con- 

 traction from successive changes of tempera- 

 ture, the rails slipping in the direction of least 

 resistance; that is, expanding down hill, and 

 contracting up hill. In both cases there is 

 generally little difficulty in arresting the move- 

 ment by driving spikes into the ties through 

 the notches provided for this purpose, either 

 in the rail-flanges at or near their ends, or in 

 the angle splice-bars so commonly used at 

 joints. The rail often exerts considerable 

 force against these spikes or bolts, and has 

 been known, in some instances, to partially 



A VIEW NEAR CATANA AFTKR THE TYPHOON. 



(From La Nature.) 



but at noon had risen to 0.88. At eight 

 o'clock the wind was from east-north-east, 

 blowing gently, and at noon was from the 

 south-east. At 12.30, near the Passo Por- 

 tese, 18 kilometres from Catana, a dark cloud 

 in the form of a spout was seen to form. 

 The rotary movement was opposite that of 

 the hands of a watch, and the spout trav- 

 elled across the country from west-south- 

 west to east-south-east at the rate of 28 kilo- 

 metres (17 miles) per hour. It frequently 

 raised itself above the ground for some mo- 

 ments, and then again touched the land to 

 complete its devastation. When near Ogni- 

 na, it left the land and went to sea, where it died out. 

 The noise produced by the storm has been compared 

 to that caused by many trains of cars passing over 

 an iron bridge at high speed. There were very few 

 flashes of lightning, and only two reports of thunder 

 loud enough to be heard above the storm. Hail- 

 stones of great size fell on the northern border of 

 devastation, causing much damage. They were very 

 rough, and some were as large as oranges. One 

 weighed S^O grams. The zone of greatest devasta- 

 tion was about 27 kilometres in length (not includ- 

 ing the 5 kilometres at sea), with a breadth of 350 

 metres. Twenty-seven inhabitants were killed, and 

 five hundred wounded. Many houses were destroyed, 

 trees torn up by their roots and carried away, and 

 in one place a piece of lava weighing 8 kilograms was 



EFFECTS OF THE TYPHOON IN A CATANA OLIVE-GARDEN. 



(From La Nature.) 



cut or shear them off. The thrust is resisted by the 

 ballast in which the ties are bedded. 



A curious instance of rail-creeping, which it is diffi- 

 cult to explain, was given in the Railroad gazette, 

 Dec. 5, 1884, where it is stated, that on a piece' of sin- 

 gle track on the New- York and New-England railroad 

 near Hartford, Conn., a part of which was level, and 

 the rest on a grade of twenty feet per mile, with an 

 equal number of trains each way, one rail moved 

 down hill five feet and one inch in the course of a 

 year, and the other moved eighteen inches -in the 

 reverse direction. It has been suggested that the 

 spikes in the two ends of the ties or sleepers may not 

 have been properly alternated, thus allowing the ties 

 to turn horizontally from the correct position at right 

 angles tO the rails. 



