33 
&c., to connect the several levels, and thus creating currents of air. In some few 
cases ordinary fans have been used temporarily. Mr. Grainger suggests that, in certain 
circumstances, the owners of adjoining mines should be compelled to connect their 
workings by means of drives. If this were done, he considers that perfect ventilation 
would be secured in many cases where it is now none of the best. 
The methods adopted for securing ventilation in the Maryborough district are, 
in shallow mines — Windsails, fans, and waterfalls. In deep and extensive mines Root’s 
Blowers are used, and, in some cases, an air shaft is connected with the main shaft by 
means of drives. The local Inspector considers that a system which would combine 
the two last-mentioned methods would be the most perfect. 
In the collieries of England it was until recently the usual practice, accord¬ 
ing to Mr. Hunt, the author of British Mining, “ to fix a furnace at the bottom of one 
shaft so as to rarefy the air, by which it was made to ascend. This is called the 
‘ upcast’ shaft. Consequently the colder external air, which is of greater weight, then 
descends another shaft, which is called the ‘ downcast shaft,’ and by well devised 
arrangements the current of air is circulated through all the devious windings of a 
colliery. The furnace system of ventilation is, however,” continues Mr. Hunt, 
“ rapidly passing out of use, mechanical ventilation having been proved to be much 
more economical and effective. Where the colliery has not two shafts—a state of 
tilings which is being discontinued—it has been the. custom to obtain the same result 
by dividing the single shaft by a 1 brattice,’ which may be either of prepared cloth 
or a division of thin boarding. In either case it is not 
difficult to produce an upward flow of air from the depth 
of the pit, and consequently to establish a downward 
current of fresh atmospheric air.” 
A sketch of the “ Anemometer,” au instrument for 
determining the rate at which air travels through the work¬ 
ings of a mine, is here given. “ It consists essentially,” says 
the author of British, Mining , “ of six vanes made of thin 
sheet brass ; these are delicately mounted on a centre 
moving freely within a brass ring. It is carried by the 
handle, and indicates the most gentle current, the rate at 
which the vanes revolve being noted by the index shown in 
the centre of the figure.” 
On the subject of ventilation, Mr. William Buttle, the prolific inventor, of 
Sandhurst, writes— 
As ventilation in mines is occupying the attention of the miners, I very much wish to mention that 
I have deposited, at the office of the Miners’ Association, a caso or tube in which a spiral screw is caused to 
revolve with very great rapidity. The blades being somewhat similar to the screw propeller of a steam-ship, 
the plan needs very little further description than to say that the screw is not continuous, but only at 
intervals on the spindle, therefore the design is not expensive. I have volunteered to attend at any meeting 
and fully explain the principle of the proposed ventilator, which cannot fail, if properly applied in the 
manner 1 will be glad to direct. 
Mr. Inspector Grainger, having been requested to report on this contrivance, 
writes — “ The suggested mode of ventilation would not be at all practicable. I have 
examined the model and cannot recommend the apparatus, as I am satisfied it would 
not answer. The inventor himself can only say that he considers 1 it should be good, 
judging from the principle of its construction.’ ” 
The following extract from Iron describes an improved fan for mine ventila¬ 
tion — 
At a meeting of the Manchester Geological Society, in January last, Mr. Cockson read a paper 
descriptive of the construction of a new fan he has designed. Ho has termed it the “ Silent Guibal,” for 
which ho claims that whilst it has the great advantages of the Guibal type, it is at the same time a silent 
non-vibratory fan like the Schiolo, and can be constructed of considerably less dimensions than would be 
required for an ordinary Guibal. 
The special advantages which Mr. Cockson claims for the fan, ho sums up as follows:_(1.) That 
fans of this typo, of from 12 to 20 feet in diameter, are able to do, at the same blade-tip speed, just as 
much work as any Guibal fan of the usual size, of say from 30 to 50 feet in diameter. (2.) That, on 
account of their less size and weight, they are not so liable to break-down and injurious straining, and, for 
the same reason, are much more economical than the larger Guibal or any other type of fan. (3.) They 
are less costly to erect, on account of the less size of the fan-gearing, and the requisite foundation, excava¬ 
tion, &c., than a Guibal would bo, to do the same work. (4.) They can be made as small and light as the 
Schiele, and will givo equal water-gauges and quantities of air, at an average of two-tliirds of the speed 
that would bo required by the Schiele to do the same work. 
JS 
