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Tlie ci(//('/( ;)'(//( is ly niriins of Oapt. Skyring's Clinometer. The little 

 card he exhibited, with its iilunimct line, soahst, and means of calculation all 

 apparently complete. Tlie angle of elevation is taken by looking along the 

 npper edge of tlie card, and the measured distance to the object is multiplied 

 by the four figures opposite the number of this angle in the table given. 

 This Clinometer for any real accuracy would require not only a very steady 

 hand, but two observers, that whilst one takes the angle tlie other may watch 

 the plumb line, and mark it. The smallest unsteadiness of the hand would 

 completely up.«et its accuracy, a fact which, it is to be feared, proves it to be 

 little more than a mere pl.iy tiling. It is small, however, and is carried readily, 

 but the compound array of figures on the scale, added to the other difficulties, 

 is not reassuring. 



There are, doubtless, other "Clinometers" of varying kinds, but all of 

 them require this secondary calculation, which makes an observer not 

 naturally fond of figures anxious to measure the distance afteiwards in 

 some other way, to be sure that he has calculated the result lightly (laughter). 



He would go on, therefore, at once to the ninth method, and the only one 

 that is at once simple and mathematically accurate. It is the instrument 

 Mr. Wells has invented, and which he had then the pleasure to exhibit to 

 them. This instrument they could see consists of a geometrical square upon a 

 stand, with a pivot and plummet line from the top corner. It may be called 

 the quadrant squared. It will measure the exact height of any given object, 

 a tree, a steeple, or a monument, and this whether you can approach the base 

 of it or no*^, and whether, moreover, you are level with the base of the 

 object, or above, or below it. It will give you the exact breadth of a river, or 

 if you please, the inclination of a hill. In short, it will do what any other 

 scientific instrument of a similar kind cun do, and something considerably 

 more. Herein consists its merit and originality. It does all its work without 

 entailing the necessity of any second.T,ry calculations whatever. It gives the 

 rf suit at once in the form you wish it. If you want to know, for instance, 

 the exact height of any given object, in taking thsiobservation, you had only 

 to measure the base, set the instrument to the top of the object, and the 

 point where the ijlunimet line crosses the distance marks at once on the lower 

 border the exact height. "Ah! that is takins the angle of elevation in the 

 ordinary way," they might say, and so it was, no doubt, but it did not note 

 the angle ; instead of that, it gave you at once the exact measurement you 

 required. The Quadrant and all other instiuments based upon it take the 

 angle of elevation, and having marked the angle, and ascertained the measure- 

 ment of the base, they leave you to transfer it to paper and calculate the result 

 in a more or less intiicate fashion. One of his instructions fiom Mr. Wells 

 was not to mention " angles ;" you did not get them, and did not want them, 

 since his instrument made all the calculations for you, and saved you from 

 the fear of erroneous multiplication. " Talk of observations, au-, and i.ot 

 angles," said Mr. Wells, "and it will prevent confusion," 



