32 
Referring to this gate, the local Mining Registrar remarks : — “ It is the most 
perfect contrivance I have seen to prevent falling down a shaft from any underground 
level, and I know of at least one fatal accident which could not have taken place had 
these gates been in use.” 
No doubt the contrivance is an admirable one, but either bars or gates will also 
afford adequate protection against accidents of this kind if properly attended to. 
When bars are used there should be two instead of one at each entrance to the shaft, 
the first at a height of 2 feet, and the second at a height of 4 feet, and they should he 
fastened to the props at one end, as shown in the sketch of bars used in the Garden 
Gully United Company’s mi tie. There, however, only one bar is used, which is a 
mistake. Two feet is recommended as the proper height from the floor for the first 
bar for the reason that when the plat is not in use a bar so placed, below the second 
bar, is an absolute protection against a man falling down a shaft, while, by removing it 
when the plat is in use for hauling, &e., the trucks can pass under the second bar, 
which latter will not only afford considerable protection against falling down the shaft, 
but will also serve the platman to lay hold of when pulling out the trucks. 
When gates are used there is a great difference of opinion as to whether they 
should be self-closing or not. The weight of evidence seems to he against the sell- 
closing principle on the grounds that an accidental or untimely swing might push a man 
back into the shaft, also that if the gate were kept closed it would be extremely incon¬ 
venient for hauling trucks, bringing up timber, &c. On the other hand, a jury 
recently empanelled, in connexion with the fatal accident at the United Ajax mine, 
Campbell’s Creek, added a rider to their verdict of accidental death to the effect that 
all gates or doors to the entrances to shafts should be self-acting, and that this should 
be made compulsory by law. As in the case of rival safety-cages, however, I think 
that the time has not yet arrived when a final decision as to the respective merits of 
the various contrivances can with safety be made. Doubtless, when tlie different 
modes of providing safeguards against accidents adopted in the several mining districts 
are made known by means of this and similar publications, mining managers will 
select that appliance which seems most suitable to their requirements. In the mean¬ 
time, if they could be induced to insist on having such appliances as are already in use 
properly attended to, a corresponding decrease in the number of accidents would be a 
sure result. 
At my request, Mr. Caleb Thomas, Mining Surveyor, Sandhurst, has forwarded 
sketches (re-produced here) of different styles of arrangement of gates, bars, and safety- 
catches, used in some of the mines at Sandhurst. Mr. Thomas states that he can find 
no instances of self-acting gates in use underground in the Sandhurst mines. 
VENTILATION. 
The subject of properly ventilating mines received a good deal of attention 
during the year, and, in connexion with it, the equally important subject of dispersing 
the fumes arising from the use of nitro-glvcerine compounds in blasting. From the 
reports of the Inspectors, it appears that the mines throughout the colony generally, 
with very few exceptions, are well provided for in the matter of ventilation. Where 
the usual means of securing a supply of fresh air, namely, by sinking winzes, or 
putting up rises to connect the different levels, are not sufficient, Root’s Patent 
Blowers are, in many cases, used with excellent effect. 
In the Castlemainc district the Senior Inspector of Mines reports that the modes 
adopted for ventilating mines are—(1) Root’s Blower, (2) ducts, (3) air-courses, and 
respective sizes. The largest sizes are equal to the requirements of the most extensive 
mine. The supply of air can be regulated by the speed of the fans being increased or 
spec 
decreased. 
In the Sandhurst district the Inspector (Mr. Grainger) reports that there is 
no machinery used for ventilating the mines. The modes adopted are—Sinking winzes, 
