SCIENCE LETTER FROM PARIS. 739 



varies greatly. At some points where large consumers mine their own coal, the 

 cost to them is even less than sixty cents per ton, while small consumers at dis- 

 tant points have to pay at times as much as $9.50 per ton, as may be seen in our 

 regular trade reports. 



Our gold and silver mines turn out annually about seventy five million dol- 

 lars worth of the precious metals, or only a little more than one-fifth of our coal 

 industry. According to Mr. James M. Swank's preliminary census report, the 

 value of the products of the iron and steel works of the United States was close 

 upon three hundred millions of dollars — less, therefore, than the value of the pro- 

 duct of our collieries. Our farmers raise annually about three hundred millions 

 of bushels of corn, which, bringing at an average one and a quarter dollars a 

 bushel, makes the average value of the crop three hundred and seventy-five mill- 

 ions of dollars, or about forty millions more than the sum realized by the sale of 

 '* black diamonds." Directly and indirectly, in the mining, transportation, and 

 distribution of coal, the trade supports more than four millions of our people.— 

 Coal. 



CORRESPONDENCE. 



SCIENCE LETTER FROM PARIS. 



Paris, February 27, 1882. 



The scientific world here is very much occupied with the subject of nervous 

 affections; also, of the curious phenomena to which they give rise and that may 

 be included under the generic titles of hypnotism and magnetism. Dr. Dumont- 

 pollier, of the Hospital de la Pitie, has conducted some very interesting experi- 

 ments upon patients, calculated to throw not a little light upon those complex 

 phenomena vaguely denominated animal magnetism, somnambulism, etc. It is 

 necessary to separate the true from the false in mesmerism. The subjects oper- 

 ated upon in the Hospital de la Pitie, suffer from nervous disorders more or less 

 complex. Some have one side of the body insensible, others the entire system so 

 affected that they can be cut or burned with impunity. Often they appear in a 

 cataleptic condition, that is, the members, while retaining their suppleness, remain 

 in the position imparted to them. Very singular attitudes can thus be given. 



There are patients with whom the lethargic state arises suddenly and con- 

 tinues during several hours, days and even weeks, while again with others the 

 nervous attacks are of a most extraordinary energy; the members contract in such 

 a manner as to display frightful contortions ; often the body is bent in two like 

 the arc of a circle, with the head and feet for points. Occasionally there is an 

 excess of gayety or of fury ; of eccentric attitudes and startling hallucinations. 



