OF AKTS AND SCIENCES. 299 



Voted^ That Professor Eustis's plan be referred to a special com- 

 mittee. 



Voted, That Hon. R. C. Winthrop, Professor Peirce, J. I. Bow- 

 ditch, Esq., Mr. G. B. Emerson, and Professor Levering be that com- 

 mittee. 



Dr. C. T. Jackson exhibited a specimen of cannel coal from 

 the Peyton coal mine, situated on a tributary of the Kenhawa, 

 in Virginia. He stated that the coal-bed is horizontal, and 

 from six to eight feet in thickness ; and called attention to 

 the electrical attraction which is developed in the coal by 

 friction, a property which he had observed in a few instances 

 in coal taken from other mines. 



Dr. W. F. Channing remarked, " that the arrangement of 

 the Municipal Fire Telegraph, now approaching its completion 

 in Boston, presents a very close analogy with the nervous sys- 

 tem of the individual. This was the result of no theory, but 

 a practical necessity, in order to unite the various parts of the 

 Municipal system by an intelligent and cooperative law. 



'' Thus in the Fire Telegraph there is a centre which is the 

 brain, the common reservoir of nervous or electric force for the 

 whole system, presided over by an intelligent will (the watch- 

 man of the central station). From this centre radiate two 

 classes of electric conductors or nerves. The first of these, 

 the ' Signal Circuit,' conveys impressions to the centre, and 

 is ^afferent,'' ^ sensitive.^ The second of these, the 'Alarm 

 Circuit,' conveys impressions /rom the centre, and is ^ efferent,^ 

 ' motor. ^ When any disturbance occurs at the circumference 

 of the system, it is signalized from the 'Signal Boxes,' which 

 are the ' sensitive extremities ' of the sensitive conductors to 

 the centre ; from which, after an act of intelligence and voli- 

 tion, an impulse to appropriate or corresponding action is in- 

 stantly sent over the motor nerves or conductors to the various 

 belfries, where the electric or nervous agent animates the iron 

 limbs, by means of the contraction of electro-magnetic m,us- 

 cles, thereby releasing powerful machinery to strike a single 

 blow upon each of the bells. By a combination of such blows, 



