ON THE RAINFALL IN THE BRITISH ISLES. 
From back tube-plate to back of fire-box. 
From crown of furnace to top of fire-box. 
Number of air-holes in furnace fronts and 
door. 
Diameter of each. 
Is there a slide on these ? 
From top of fire-box to crown of boiler. 
From top of fire-box to top of steam-chest. 
Size of steam-chest. 
Steam room in each boiler in cubic fect, 
With water-level, inches above fire-box 
crown. 
Are the boilers dry-bottomed ? 
Number of tubes for each furnace, in height. 
Ditto in width. 
Ditto, left out for stays. 
Length of tubes. 
Inside diameter of tubes. 
Material. 
Chimney—diameter at uptake. 
Number of chimneys. 
Height from fire-bars to top of chimney. 
Superheater. Is there a superheater ? 
At what temperature is the steam used ? 
Temperature of smoke in chimney. 
Saltness of water in boilers. 
Is there a feed-heater ? 
Temperature of the feed water. 
Temperature of the hot-well. 
Vacuum maintained. 
What is the difference between the inches 
in the vacuum-gauge and the inches on the 
ship’s barometer taken at the same time ? 
Pressure of steam in boilers. 
When at full speed, what is the difference 
between the steam-gauges at the boilers 
and near the cylinders ? 
Is there a good command of steam ? 
Is there flame in the smoke-box ? 
Reyolutions of engines per minute. 
Please enclose indicator diagrams, and mark 
each one thus, or in some other intelligible 
way :— 
AT/G|S|V|R/K|D Cc Ship’s 
Rushby | Name 
Park and 
14/23 45/12/13) 74 Date 
298 
which reads thus:—Aft engine top of 
piston; Grade of expansion 3; Steam- 
gauge 14; Vacuum-gauge 23; Revolu- 
tions of engine 45; Speed of vessel, in 
knots, per hour 12; Mean draught 18 ft.; 
Rushby Park Coals, per hour, 73 ewts. 
If the speed of vessel be given in statute 
miles, write M instead of K. 
Instead of AT write AB, FT, FB, as the 
case may be. If convenient, after V in- 
sert a which reads, Barometer 29 in. 
You are also requested to fill up as many 
lines of the following Tables as you have 
an opportunity of doing. 
TABLE OF PERFORMANCE UNDER TRIAL, 
UNDER STEAM ALONE,UNDER SAILALONE, 
AND UNDER STEAM AND SAIL COMBINED, 
Number of Trial. 
Date. 
Place. 
Ship’s course 
Direction of wind. 
Force of wind. 
State of sea. 
Duration of trials. 
Area of sail set. 
Description of sail set. 
Average speed per hour. 
Consumption of coal per hour. 
Quality of coal. 
Indicated horse-power. 
Diagrams enclosed, No. 
Draught of water. 
Pitch of screw. 
Screw covered. 
Grade of expansion. 
Steam-gauge. 
Vacuum-gauge. 
Barometer. 
Revolutions per minute. 
Number of furnaces at work. 
Nore.—Trials Nos. are under steam 
only, and Nos. under steam and sail 
combined, 
On the Fall of Rain in the British Isles during the Years 1860 and 
1861. 
By G. J. Symons, M.B.M.S. 
Brrore entering on the consideration of the rainfall during the last two 
_ years, it will be well to offer a very few preliminary remarks on the various 
causes which affect the amount of rain collected, and also briefly to state 
in what manner the information given in the following Tables has been 
verified. 
_ The first requirement is obviously that the gauge should be rigorously 
accurate, and placed in a suitable position ; but it is equally obvious that the 
satisfactory fulfilment of these conditions can only be determined when every 
