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we observed before, electricity firids considerable obstruction where the conductor is interrupted.
For an edifice of a moderate size, one conductor, in the manner already described, is perhaps sufficient; but in order to secure a large building from sustaining any damage by lightning, there should be two, three, or more conductors, in proportion to the extent of the building*
In SHIPS a chain has often been used for this purpose, which, on account of its pliableness, has been found very convenient, and easy to be managed among the rigging of the vessel ; but as the electricity finds a great obstruction in going through the several links, for which reason chains have been actually broken by the lightning, so their use has now been almost entirely laid aside; and, in their stead, copper wires a little thicker than a goose-quill have been substituted, and found to answer very well. One of these wires should be elevated two or three feet above the highest mast in the ves-sel; this should be continued down the mast, as far as the
deck -* Mr ROBERT PATERSON of Philadelphia, proposes as an improvement on conductors, first to insert, in the top of the rod, a piece of the best black-lead, about two inches long, and terminating in a fine point which projects a little above the end of its metallic socket; so that if the black-lead point should, by any accident, be broken off, that of the rod would be left sharp enough to answer the purpose of a metallic conductor. His second inter tion is, to facilitate the passage of the electric fluid from the lower part of the 'rod into the surround. ing earth. In many cases, it is impracticable, from the interruption of rocks and other obstacles, to sink the rod so deeply as to reach moist Earth, or any other substance that is a tolerably good conductor of e. icctricity. To remedy this defect: Mr PATERSON propo:es to make the lower part of the rod, either of in or copper, which metals are far less liable to corrosion or rust, than iron, when lying under ground; or, which will answer the purpose still better; to coat tha: pan of the conductor, of whatever metal it may consist, with a thick crust of black-lead previously formed into a paste, by being pulverized, mixed with melted sulphur, and applied to the rod, while hot. By this pre. caution, the lower part of the rod will, in his opinion, retain its conducting powers for ages, without any diminution. 13:14
In order to increase the surface of the subterraneous part of the con. ductor, he directs a hole, or pit, of sufficient extent, to be dug as deep as convenient; into which a quantity of charcoal should be put, surrounding the lower extremity of the rod. Thus, the surface of that part of the conductor, which is in contact with the earth, may be increased with little trouble or expense; a circumstance of the first importance to the security against those aceidents as charcoal is an excellent conductor of electricity, and will undergo little or no change of property, by lying in the earth for a long series of years.:
WILLIca's DOMESTIC ENCYCLOPÆDIA.
A Father's Advice to his Son.
MAY youth's first hope, my manhood's treasure,
IV My dearest innocent attend; ' .?
A father's loveliest name is Friends in
Worth more than royal grants, receive;
Which king's have seldom power to give.no
And claim by birthright to be good.
Superior rise above the crowd ; ! -
From others' joy a friendly glow,
Throbs with a sympathetic woe.
Though wide proud Pomp her banner spreads, " An heav'nlier power Good-nature bearing,s
Each heart in willing thraldom leads. , p .
The peace-destroying streams that flow,
Look down upon the world below.
If heav'n with children crown your dwelling,
As mine. its bounty does with you,
Th' example you have felt pursue.
THE PRUDENT DECISION;
THERE liv'à in York, an age ago,
And prais'd him with their sweetest voice. ". Young Pim, the gallant and the gay,
Like ass divided tween the hay, :
Each dress'd herself divinely neat; iz
For surely Nancy, Betty, Sally,
For that, of truth, was said of Nancy: rain * And as for Sall, she was a Donna,
As fair as those of old Crotona,
To make up madam Helen's graces. ay To these, the gay, divided Pim ,, ,
Tame elegantly smart and trim;