43 
should ho handed over to the purchaser with an endorsement showing how long it was in use at each 
mine. By these means the age of each boiler could be known ; but at present, owing to the frequent 
removals of boilers, there arc no means of knowing how long they havo been in use, or what sort of water 
has been used in feeding them. 
Mr. Meekison’s suggestions cannot, of course, be adopted under the present 
Regulation of Mines and Machinery Act , but they will no doubt be taken into con¬ 
sideration in connexion with any proposed amendment of it. In the meantime, each 
of the Inspectors of Mines has been instructed that if any boiler has not, in his 
opinion, been tested up to sufficient pressure he should make a record to that effect, 
and call the attention of the manager of the mine to the fact, informing him at the 
same time that should any accident occur by reason of the defective character of the 
boiler he will render himself liable to prosecution under section 19 of the Act. The 
Inspectors have also been instructed to bring under notice every case where the 
erection of a new plant is being proceeded with, in order that an examination of it 
may, if necessary, be made by the travelling inspector of machinery before the plant 
starts to work. 
There is some difference of opinion as to whether glass gauge mountings on 
boilers are sufficient without try-cocks, but experience goes to show that no boiler 
can be considered complete without try-cocks. Mr. Inspector Meekison, in reference 
to this matter, states:— 
In addition to glass gauges, I am of opinion that try-cocks are necessary to the safety of the boiler, 
for the following reasons:— 
1. It is a common occurrence for the bottom cock of the glass gauge to get choked when working 
with muddy water, and in some kinds of mountings (especially wheel valves) there is great difficulty in 
clearing them when steam is up, and in that case all you can depend on for your water level is the try- 
cocks. In my own experience I have known this often happen. 
2. In most cases the gauge-glass mountings are fixed to the boiler, so that when the water is at the 
bottom of the glass it is at a safe height over tube, but as the cock is fixed to the boiler, at least two inches 
below the level of the bottom of glass, in the event of the glass being broken, the bottom cock may show 
water when it is dangerously low in the boiler. 
In most of the boilers I have alluded to as having only one try-cock, there has originally been two, 
but from some cause (probably one cock becoming useless, and not having another to replace it) the hole is 
filled with either a bolt or rivet. In every such case, when I drew the manager’s attention to there being 
only one cock, he admitted the necessity of two, and always agreed at once to put another one in. Where 
engineers were employed, there were always two try-cocks or two gauge-glasses in each boiler. All 
authorities agree on the necessity of at least two cocks, while some recommend three. 
Most boilers have two try-cocks attached to them, but it is a well-known fact 
that in many cases the persons in charge never use them, a circumstance which 
is specially commented on by the Board of Examiners for Engine-drivers. (See 
page 98.) 
Quite recently a boiler explosion took place at the Comet mine, Sandhurst, 
in reference to which Mr. Inspector Grainger has furnished me with the following 
report:— 
The boiler of Lansell and Mueller’s Comet mine exploded at about a cpiarter to eight a.m. on the 
24th January. An engine-driver named William Benson was in charge at the time, having commenced 
work at 7 a.m. He states everything was all right as far as he knew, and plenty of water in the glass. 
This statement is corroborated by the mining mauager, James Ilall, who, on arriving on the mine at 7 a.m., 
also went around the works, and took particular notice of the glass (this being bis regular custom), and 
saw the water up in it all right. Fortunately no injury was done to any one, and the damage was confined 
to the boiler and a small portion of the engine-house., The boiler, which was first used about 20 years 
a <r 0 , was 30 feet in length by 6ft. Gin. diameter, with §-iu. plates. The Hue of it was torn from end to end. 
It was tested last August up to GO lbs. to the square inch cold water, which is considered equal to 80 lbs. 
steam pressure. The manager’s record book, showing the test, was made on my inspection of it. The 
working pressure was 40 to 45 lbs., and the safety-valve blew oil at 50 lbs. On making my inspection I saw 
evident marks that the water was up in the glass. The cause of the explosion cannot bo accounted for in 
any other way than that the boiler was defective although it stood the tests. I may add, I cannot impute 
blame to any one. 
From the above report it appears tliat the working pressure (the limit of the 
safety-valve) was 50 lbs. According to the requirements of the English Board of 
Trade, marine steam boilers have to be tested by hydraulic pressure up to one and a 
half times the limit of the safety-valve ; but the practice of the most reputable 
mechanical engineers, in turning out new boilers, is, 1 believe, to have them tested by 
hydraulic pressure up to twice the guaranteed maximum of the safety-valve. 
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