Make an Electric Battery,” Vol.  X, No. 8; “The Induction Coil and How to Make It,” Vol.  X, No. 28; “A Simple Electrical Machine,” Vol.  XI, No. 6:  “Simple Electrical Experiments.”  Vol.  XI, No. 15; “An Electric Bell Outfit,” Vol.  XI, No. 20; “How to Make a Storage Battery,” Vol.  XI, No. 25; “Induction Coil Condenser,” Vol.  XI, No. 47; “Electric Lamps and How to Work Them,” Vol.  XII, Nos. 1 and 2; and “Electro-Motors and How to Make Them,” Vol.  XII, No. 3.

BIAS EYES.—­1.  Letters relating to business matters connected with this paper—­such as inquiries relating to advertising rates—­are the only ones answered by mail.  They must invariably contain a stamp to pay postage on such reply. 2.  Any reader complying with the rules governing the exchange department is entitled to its privileges. 3.  He is an Englishman by birth. 4.  The principal use of the bell on board ships is to denote the time of the day or night, which is done by 1, 2, 3, and so on, up to eight strokes of the bell.  The twelve hours between midnight and noon, or noon and midnight, are divided into three portions of eight bells each, the duration of time between bells being half an hour.  Consequently, during the course of each twelve hours, the same number of strokes of the bell will necessarily be used to denote three different hours or periods of time, as follows: 

1 bell at 12.30, 4.30, 8.30. 2 bells " 1.00, 5.00, 9.00. 3 " " 1.30, 5.30, 9.30. 4 " " 2.00, 6.00, 10.00. 5 " " 2.30, 6.30, 10.30. 6 " " 3.00, 7.00, 11.00. 7 " " 3.30, 7.30, 11.30. 8 " " 4.00, 8.00, 12.00.

5.  The magnetized needle of a compass has the property of arranging itself in the meridian, one end always pointing to the north and the other to the south; yet not exactly, but with a deflection or declination which varies from time to time in magnitude, and may be toward the west or the east.

A READER OF GOLDEN DAYS.  A very plain and simple method of making snow-shoes was furnished our readers in Vol.  Vll, No. 2. —­ROD AND GUN.  In Nos. 15, Vol.  I; 23, 24 and 36, Vol.  II, will be found articles devoted to the subject of camping out, which contain all requisite information regarding that form of recreation. —­DODY.  The Spanish sentence is untranslatable, several of the words being beyond the ken of any one who understands that language. —­LAWYER.  The gentleman representing your district in Congress is the proper person to whom application should be made for copies of the “Congressional Record” and Department Reports. —­J.S.T.  A portion of No. 52, Vol.  VIII, was devoted to a minute description of ice-boat building. —­A.S. 1.  California half-dollars, in perfect condition, are worth 60 or 70 cents each. 2.  It is claimed to be very efficacious. —­W.P.  Your offer is respectfully declined.  We have already provided many articles on electricity in its various forms, and from time to time will publish others by practical writers. —­NENA. 1.