28$ COMMANDER JOHNSON’S EXPERIMENTS ON AN IRON STEAM-VESSEL. 
Table X. 
Position of the different Compasses on board, with their distances from particular 
parts of the Iron-work. 
Letter or 
Mark of 
Compass. 
Position. 
Distance of the Pivot from particular parts of the iron-work. 
A. 
Quarter-deck. 
Above the deck, 5 feet 9 inches. From nearest iron beam, 5 feet Ilf- inches. 
From nearest end of spindle of wheel 6 feet 6 inches, and 3 feet 3 inches above level. 
From iron tiller, 8 feet 2 inches. From iron rails abeam, 9 feet. 
From nearest part of davits when out, 10 feet 8|, when inboard, 7 feet 1-j inch. 
From the great funnel, 39 feet 7 inches. From tafrail, 11 feet 5^ inches. 
B. 
Forecastle. 
Above the deck, 5 feet 11 inches. From nearest iron beam, 6 feet 1J inch. 
From iron abeam, 1 1 feet 2 inches. From chain cables, 6 feet on both sides. 
From iron windlass, 7 feet 5 inches. From pea of anchors, 10 feet 8§ inches. 
From the stem, 19 feet 8J inches. From great funnel, 55 feet 4§ inches. 
From end of crane, 18 feet 1 inch. From iron wire of skylight, 4 feet 1 inch. 
C. on 
glass 
legs. 
On bowsprit. 
From the iron ring at the end of bowsprit, 4 feet 6 inches. 
From iron above the stern, 6 feet 7 inches. 
From iron cat head, 11 feet 3 inches. 
D. 
On the fore part of 
the temporary poop. 
Above the deck, 8 feet 5|: inches. From tafrail, 15 feet 9 inches. 
From the large funnel, 34 feat 8 inches. 
From nearest part of davits when out, 10 feet 11 inches. 
E. 
On the after part of 
the temporary poop. 
From the deck, 8 feet 5 inches. Horizontal line to tafrail, 3 feet 3 inches. 
From nearest iron on tafrail (oblique), 7 feet 4 % inches. 
From spindle of wheel, 8 feet. From great funnel, 47 feet 10 inches. 
F. 
On the stage level with 
the tafrail. 
From iron rails over the tafrail, 13 feet 64 inches. 
From nearest part of davits, 18 feet 2 inches. 
G. 
On a plank 4 feet 
below the main gaff 
end. 
Above the deck, 20 feet 7 inches. From iron bolt in gaff end, 4 feet 8 inches. 
From the great funnel, 32 feet. 
From the iron rails above the tafrail, 24 feet 6 inches. 
I. 
On the centre of the 
temporary poop. 
Above the deck, 13 feet 4§ inches. 
Horizontal line to tafrail, 10 feet. 
From the great chimney, 40 feet. 
From the nearest part of davits, 13 feet 9 inches. 
L. 
On the poop projecting 
over the stern. 
Horizontal line to perpendicular of tafrail, 3 feet 9 inches. 
From tafrail, 6 feet 4 inches. From davit, 21 feet 3 inches. 
From the great funnel, 54 feet 3 inches. 
M. 
On the stage over the 
stern level with the 
tafrail. 
First position, 9 feet 11^ inches from tafrail. 
Second position, 5 feet 8 inches from tafrail. 
Third position, 4 feet from tafrail. 
o. 
Between the paddle- 
boxes. 
From the great funnel, 22 feet 3 inches. 
From the iron rails between the paddle-boxes, 7 feet. 
From the nearest part of the crane, 12 feet. 
P. 
Two thirds up the 
foretopmast. 
Above the deck, 40 feet 2 inches. From crane, 29 feet 3 inches. 
From the iron cap of the mast, 6 feet 11 inches. 
From the iron crosstrees, 1 2 feet 6 inches. 
Q. on 
glass 
legs. 
In the fore-hold. 
From foremost bulkhead, 9 feet 6 inches. From aftermost bulkhead, 9 feet 6 inches. 
From nearest iron beam above, 4 feet 74 inches. From ditto below, 4 feet 7 § inches. 
From sides of vessel, 9 feet 10 inches. From spindle of crane, 8 feet 4 inches, larboard side. 
S. 
In the iron sphere 
amidships. 
Above the deck, 7 feet. From great funnel, 24 feet 5 inches. 
From iron rails on paddle-boxes, 10 feet 2 inches. 
From nearest part of crane, 9 feet. 
! T - 
In the cabin. 
From foremost iron bulkhead, 4 feet 7 inches. 
From iron stove abaft, 4 feet 7 inches. 
From iron beams above, 5 feet 4 inches. From ribs below, 5 feet 4 inches. 
, 
From the sides of the vessel, 9 feet 11 inches. 
