NEW INVENTIONS. 
239 
metal, with curved and with flat portions, and through the flat portions 
they pass bolts ox rivets to secure the same to the framing of the vessel, 
turret, target, fort, or structure, in such manner that other curved plates 
may be placed over the flat portions of the first-mentioned plates, and over 
the joints thereof, to cover and protect the bolts or rivets first mentioned, 
the last- mentioned curved plates being bolted or rivetted through the first 
mentioned curved plates, or otherwise, or secured in any equivalent 
manner. By these means additional strength is obtained, and the prin- 
cipal, and, if desired, the major part of the joints and bolts, or rivet-heads, 
is protected, so that a single plate shall not receive all the force of any 
projectile or striking body, but such force be distributed over the whole 
of the plates. 
Mariners’ Compasses. — Mr. R. Alexander , patentee. — These improve- 
ments have reference to the use of compensating or adjusting media, or 
both in combination, to render the magnetic needle independent of the 
local attraction of iron or other metals, metallic ores, or compounds, in the 
ship, vessel, or other place where the compass or needle is fixed. The 
means by which the patentee proposes to effect these improvements are — 
1. By appliances of counteracting and adjusting magnets, or magnetic 
poles, upon the compass needle-card or cards, or otherwise placed ; 2. 
By the use, if necessary, of a moveable magnetic ring or rings, attached to 
the needle-card by springs or otherwise, so as to be easily removed when 
it is required ; 3. By the use of a series of magnets, placed on or in a flat 
or curved surface, with or without rims or bands of soft iron, stationary 
or revolving, above, below, or horizontal with the middle card or cards, 
or both above and below them ; 4. By the application of electricity or 
galvanism in conjunction with a part or the whole of the aforesaid appli- 
ances ; 5. By the use of one or more magnetic needle cards, and one or 
more of the appliances explained above, placed one above the other, 
revolving in union with or independent of each other on the same (or on 
distinct) pivots, or one or more of them stationary and another or others 
revolving, or any one or more of them used in conjunction with a simple 
magnetic compass card, as commonly used, only revolving on distinct 
pivots, whilst a part may be stationary ; 6. By the use of aluminium 
metal for the needle-cards, or india-rubber composition, commonly called 
ebonite, for the cards, rims, bowls, hoods, boxes, binnacles, and gimbals, 
and other parts of the compasses and appliances, or an admixture of steel 
filings or cuttings in the india-rubber composition for some of these, or 
the whole of the said parts above referred to ; 7. By the use of hollow iron 
spheres or spheroids to encompass a part or the whole of the apparatus ; 
8. By the application of a spring pivot or point on which the magnetic 
compass-card revolves, and springs to an outward or second gimbal to 
the bowl ; 9. By the application of the invention to electro-magnetic 
instruments. 
Anchors. — Mr. W. Rodger , patentee. — These improvements in anchors 
have reference to those parts which are usually termed the crown, the 
arms, and the palms, and the object in view is, to obtain a greater 
amount of strength and holding power with a given weight of iron than 
is possessed by anchors of the ordinary construction. The additional 
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