Daily American telegraph. [volume] (Washington [D.C.]) 1851-1852, 1852-08-03
Protection from lightning.

FNHE undersigned being the duly appointed Agent Of
srRAfrs ELEOrRlcAS AND ELECTRO MErALuhalsr ldazl
these superior Rods of Sprawsted Carbonzed Annealed
Iron, with Zine Protectors, and Eectroposve elements
combined In their manufacture; thus rendering them
to copper conductors They In tenee lengths with
accurately fitted brass screw connecting joints an entire
new style OF metallic paented) attachments, for brick or
frame buildings also, glass solaers of novel and nge
NOUS construction (patened forming lock; the whole
mounted with solid platinum silver point (patented)
twelve inches long, at the with three angu
lar negative magnets which the power TO an extra
ordinary extent OF opposite elements OF ne
most fearful Thunderstorm and embrace the entire perec
ton of science up to the present times the whole constitu
ting the most magnificent aud perfect silent conductor ever
presented to the public.
Safety has not been compromised by aording these
ceent rods at such low rates. the greatest attention has
been given to their construction be readily attached
The astonishing power Of the negative magnets in dscharg
Ing the air of its opposite elements has been clearly demon
have shown but slight results though placed under the
conditions In fact they gather and silently discharge
electricity from the atmosphere when you would scarcely
suspect any being present
These being secured by double letters pa
tent you hereby cautioned against laying yourselves
LIABLE by purchasing OF those who not authorized or
who substituting inferior limitations All agents duly
none CHARLES W. HEYDoN,
Washington City.
do hereby certify that have app lied various powerful
chemical reagents to Spras Patent Points for Lightning
that the results these experiments convince me
that they will resist the action of atmospheric causes and
thereby the extremity sharpa condition most es
enta to protection against lightning The reagents used
in the above experiments were solution chloride of
dium common acetc acid sulphurc acid and hydro
choric acid. With the first there no action on the
metal with the several acids, there was very sg fact
sufficient to show that atmospheric influences would have
no sensible effect.
JOHN LECoNTE, Prof of Nat. Phil. ct Chem
UNIVERSITY OF Ga. October 8, 1850.
The Lightning Conductors of Mr. spra offered to me,
we'll calculated to perform the office for which they are
intended. Yours, truly Prof ROBT. PETER
LEXINGTON, KY, February 20, 1850.
CHICAGO, September s. 1850.
This may certify that have examined somewhat cr-
cally James Spras Patent Lightning Rods, and that am
opinion constructed scientific principles For
combining durability, cheapness and efficacy, deem II
equal and think SUPERIOR to any other rod ever offered
for my inspection Prof JAS V. q. BLANEY
AUGUSTA, (GA.) November II, 1850.
This will certify that have examined the Lightning
Rods Metallic Points, and Isolang Attachments, manu-
featured by Mr. Spra and regard them az constructed In
conformity laws Of the electric d and the
metallic compound constituting the Points promisng
the result of several tests TO which they submit
ted to resist for the action OF those
most likely to corrode them. A. MEANS,
Prof Phys &C., Emory College, Ga, and Prof Chem and
pharm., Medical College, Ga.
The Lightning Conductors put up by Mr. Henry Smith,
Of this city, the plan Of Mr. Sprat appear to me to be
very well devised and in point Of mechanical construction
are the best have
1t Is be hoped that the Of these Rods may become
general important auxiliary defence against danger
which bs regarded of ordinary magnitude to
which all buildings are liable. r. sILIMAN, Jr,
Prof of Chem. in the University Of Louisville.
LOUISVILLE, January II, 1851.
All orders left at ANDREW DUFFYS Stove Mandatory,
7th street. will be promptly attended to; or at GEORGE
BELLS Alexandria, Va corner OF King and st. Asaph sts
ap 14-tf