178 Miscellanies. 
to admit of their being easily brought together or separated at pleas- 
re. 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 
rog.—Jour. des Prog. des Sciences et Med., Tom. HH, 1830. 
2. Safety of steam engines—The societé d’Encouragement of 
Paris have decided upon granting two 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 al] danger from explosions.” 
Each of these premiums shall be two thousand francs, and decreed 
to any Sapte or Foreigner, who shall be deemed most worthy 
fi it. 
The Bani 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, ° 
models, reports or certificates must be sent before the first of July: 
1831.—Ann. des Mines. 
3, Violent thunder storm in Switzerland.—At the meeting of the 
Helvetic society last year at St. Gall, an account was given by 
Watt of a storm in the Canton of Basle, on the sixteenth of July, i830. 
The road which leads from Soleure to Basle by Wangen, passe 
over the Haunstein, on the north eastern extremity of the Jura. 
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; 
along which the road passes, and empties into the Ergeltz, which, iD 
turn, discharges itself into the Rhine. Ina few moments these stream* 
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 ‘valleys 
the bridges and farms were ruined. At Waldenburg, it demolished 
all the houses in the lower part, and inundated those in the uppe™ 
Proceeding onward, the villages of Oberdorf and Nulerdorf were s00? 
Jeft a licep of ruins. Qn the village of Hollstein, the devastating tor 
