316 



with force sufficient to overcome the work to be done. To the shaft of the 

 mill a force-pump is connected, and this pumps up the water to a I'eservoir 

 placed at a certain altitude. A supply of water at pressure is thus 

 obtained, which is found very useful on the farm for various purposes ; and, 

 having a certain head upon it, it is invaluable for the extinction of fires. 

 Now, if this arrangement was in use, the water thus under pressure might 

 be arranged to be sufficient to work a small turbine, or a small water pressure 

 engine. The power thus obtained, would be obtained at a comparatively 

 small cost ; there is no expense in keeping it up, as in the case of a steam 

 engine ; the only expense would be in keeping the apparatus in repair, which 

 would not be much, as at the slow speed with which the work would be done 

 there would be comparatively little wear and teai-. True, the power of the 

 windmill would be intermittent, in calm days not working at all ; but by 

 storing up the water, which it would pump up in an elevated reservoir, the 

 power would be available at any time, thi'ough the intervention of the turbine." 



I think the above extract is likely to give New Zealand settlers a valuable 

 hint as to a mode of supplementing a limited water power without the necessity 

 of going to the expense of purchasing a steam engine, and afterwards main- 

 taining it, at a great annual chai'ge for fuel and management. 



It may be said, why not apply the wind power dii-ect 1 The reply is 

 obvious. The wind power is not a steady power, and for working flax, 

 machinery di-iven by it might be standing still for days together, with the 

 " hands " engaged standing idly by. 



In the depressed state of the flax industry, it is desirable that we should 

 study every economy in the production of the fibre. 



Art. LXI. — On the Use of the Semicirculm' Protractor, with a Descrijytion of 

 an Imjoroved Form of that Instrument. By James Stewart, C.E., Assoc. 

 Inst. C.E. 



{Read before the Auckland Institute, November 7, 1870.] 



Any method by which a series of lines forming given angles with each other, 

 or bearings with the meridian, can be expeditiously and acciirately plotted, 

 ought to be of interest to many besides the professional surveyor or dravights- 

 man. It is presumed that this will be granted so readily, that the writer deems 

 it unnecessary to apologize for bringing before the Institute a subject of 

 apparent professional detail, or to enumerate the pursuits, in facilitating which 

 the Semicircular Protractor can materially assist. 



So far as the writer knoAvs, the protractors in almost universal iise are 

 circular, and are either of lithographed paper or more elaborate instruments of 

 brass. In either case the method of using them is the same. The instrument 

 is fixed down on the drawing paper, and all the bearings required are marked 



