178 Miscellanies, 



to admit of their being easily brought together op separated at pleas- 

 ure. He then suspended a prepared frog to the upper wire, and 

 placed the hind feet of it on the lower wire. Thus prepared, when- 

 ever the disks were plunged, one of them into the red ray, and the 

 other into the violet, and the extremities of the two wires were 

 brought into contact, contractions took place in the muscles of the 

 frog. — Jour, des Prog: des Sciences et Med., Tom. II, 1830. 



2. Safety of steam engines. — The societe d'Encouragement of 

 Paris have decided upon granting tv/o premiums ; — " One to him, 

 who shall perfect and complete the means of safety, which have hith- 

 erto been employed or proposed, against explosions of steam engines 

 and other boilers, or point out better ones ; the other, to him, who 

 shall invent a form, and a construction of the boiler, which will pre- 

 vent or annul all danger from explosions." 



Each of these premiums shall be two thousand francs, and decreed 

 to any Frenchman, or Foreigner, who shall be deemed most worthy 

 of it. 



The method proposed must have been tested by, at least, six months' 

 trial in a steam engine of high pressure, of ten horse power or larger, 

 or on a boiler of equal force. The efficacy of the proposed improve- 

 ment must be duly authenticated, and the inventor must renounce any- 

 intention of securing patent priviliges. The memoirs, designs, or 

 models, reports or certificates must be sent before the first of July, 

 1831. — Ann. des Mines. 



3. Violent thunder storm in Sivitzerland. — At the meeting of the 

 Helvetic society last year at St. Gall, an account was given by M. 

 Watt of a storm in the Canton of Basle, on the sixteenth of July, 1830, 



The road which leads from Soleure to Basle by Wangeii, passes 

 over the Haunstein, on the north eastern extremity of the Jura. On 

 the highest point of this route, the clouds collected from different 

 quarters, and poured their contents upon the northern side of the 

 mountain. The Hauptbach, a small brook, runs through the valley, 

 c^long which the road passes, and empties into the Ergeltz, which, in 

 turn, discharges itself into the Rhine. In a few moments these streams 

 were transformed into enormous torrents from six to ten feet deep. 

 The water, bearing with it wood and stones, overthrew every thing 

 in its passage. The roads were destroyed from the top of the valley, 

 the bridges and farms vfexe ruined. At Waldenburg, it demolished 

 all the houses in the lower part, and inundated those in the upper. 

 Proceeding onward, the villages of Oberdorf and Nulerdorf were soon 

 left a heap of ruins. On the village of Hollstein, the devastating tor- 



