118 REPORT 1851. 



To the lower end of the iron axle a portion of a brass sphere was attached in such a 

 manner as would admit of a dial- plate divided into 24 parts, to represent as many 

 hours, being brought with its centre vertically over the north pole, where it might 

 be fixed by a thumb-screw within the sphere, or at any latitude down to the equator. 

 To the upper end of the axle was fixed a pulley, having two grooves, round each of 

 which, in contrary directions, a small cord was passed, which was then carried 

 through a small hole into the interior of the pulley, where it was secured. The ends 

 of the cord were fastened tight to pillars secured one to each end of the bottom board. 

 By this arrangement the model sphere was made to rotate by moving the waggon 

 along the railway. Attached to the waggon, and exactly coinciding with the centre 

 of the sphere, was an universal joint, from which a radial bar of steel extended through 

 and a little above the dial, where it received a steel cross-bar that might be set in 

 any direction to represent the plane of the pendulum's oscillations. Mr. Roberts 

 contended that the phrenomena in nature happened as this model showed, viz. that 

 the pendulum would perform a revolution in 24 hours in all latitudes above 45°, or 

 even a little below that latitude, after which it would reciprocate. 



The second model consisted of a quadrant, upon the edge of which was a brass 

 dial divided into 24 parts to represent hours. Upon a pin or stud, fixed in the centre 

 of the dial, was a pointer, to one extremity of which a plummet was suspended, the 

 object of which was to keep the pointer parallel to any plane that the pendulum might 

 be caused to oscillate in ; whilst the plummet will always be in the direction of the 

 centre of the earth's gravity. To show the operation of the pendulum in all latitudes, 

 the quadrant had been mounted upon a stand with pieces of wood jointed in such a 

 manner that the parallelism of the pendulum to any plane in space might be seen by 

 inspection of the model. 



On a simple method of applying the Power of Wind to a Pump, for the pur- 

 pose of Irrigation, as put into practice at the Cape of Good Hope. By 

 Professor P. Smyth. 



On an Improved Modification of the Reservoir for Gold Pens. 

 By James Thomson, C^. 



A slightly w^orn quill pen is generally esteemed the best instrument for affording 

 quickness and ease in writing. The leading objection to steel pens is that they 

 scratch the paper ; if not when new, certainly after they have been exposed for a 

 short time to the corrosive action of the ink. In gold pens the points may be made 

 of any foim, either fine or blunt ; but if they be made as blunt as would be desirable 

 to imitate the slightly worn quill pen, it is found that the ink is discharged in much 

 too great quantity on the paper, and that thus the writing is blotted, and inconve- 

 niently frequent dipping of the pen is required. The reason why the capillary at- 

 traction has so much less power to hold up the ink in the gold pen than in the quill 

 one, is to be found in the difference of form of the two pens. In the gold pen the 

 part to which the ink adheres requires to be tapered very much to produce the re- 

 quisite flexibility in so rigid a material. In the quill pen, on the other hand, the 

 semicylindrical part extends very nearly to the point, and contains the upper part of 

 the drop of ink. The hollow form thus given to the surface of the drop of ink in the 

 quill pen has, according to the laws of capillary attraction, a powerful tendency to 

 sustain the ink, while the convex form of the drop in the gold pen tends to force the 

 ink down on the paper. 



The objections thus arising to the gold pens may, however, be more than obviated 

 by the application of a reser\'oir consisting of a plate or tongue of gold placed in the 

 hollow of the pen so as to cover the part to which the ink adheres. Now a reservoir 

 nearly fulfilling all the conditions that could be desired has been for some time in 

 use, having been patented by Mr. Riddle and manufactured by Mr. Mordan. There 

 are however some objections to which that particular form of reservoir is subject. 

 It does not, for instance, admit of being opened wide enough to be easily cleaned ; 

 and from its large size it contains more ink than it can hold up with sufficient force. 

 The new modification, which is the subject of the present paper, is free from these 

 objections and appears to be decidedly an improvement. There is a plate or tongue 



