52 POPULAR SCIENCE MONTHLY. 



largely social. A recent announcement comes as a surprise to 

 everybody, that the , Japanese records prove that six hundred years 

 ago kites were used by this people in war time for carrying up 

 observers to detect the position of an enemy's forces. 



After all, America must be credited with the first application of 

 the kite to scientific investigation; Ben Franklin — as all intelligent 

 persons know — being the experimenter from whose discoveries large 

 results in electrical science have proceeded. Numerous experiments 

 in this direction followed his initiative, in France and, with less fer- 

 vor, in England; while in Russia a zealous scientist lost his life by 

 his temerity with a metallically equipped kite in a thunderstorm. 



Perhaps this catastrophe was the cause of the abandonment of 

 this method of investigation of the upper atmosphere, for nothing 

 that attracted much attention was again accomplished by kites until 

 the year 1894, when the Blue Hill investigations began. 



The first year's work at this observatory (a private institution, 

 established and sustained by Mr. A. Lawrence Botch, from public 

 spirit) made little addition to the knowledge previously acquired by 

 amateur fliers; but the succeeding years show marked advances. 



At present it is usual, in flying flat kites, to send up several 

 on the same main line. Generally a small kite is first sent up, and, 

 when this is securely mounted, a larger one, attached to the main 

 line perhaps a hundred feet below by about that length of its own 

 string, is started after its leader. 



As the number of kites in the tandem increased, more strength 

 was required at the lower end of the line to withstand the pull; so 

 the reel quickly became an important part of the apparatus. The 

 labor of winding was such that the reel was provided with a crank, 

 and mounted more and more strongly, and a recording wheel and dial 

 were soon added to measure the line as it ran out. The apparatus 

 was then made portable by combining it with a sort of wheel- 

 barrow. 



IS^ot only the number of kites but the height of their ascent in- 

 creased the strain on the wheel, and one after another — though of 

 solid oak- — were crushed by the drawing of the concentric layers in 

 winding in, esjjecially after the change was made to a metal string. 



Last season (1897) a unique reel was introduced in which a two- 

 horse power steam engine took the place of human muscle for wind- 

 ing in. Steam is supplied by a boiler heated by oil spray as fuel, 

 these and the reel proper being mounted on the same portable base. 

 Included in the winding apparatus is a strain-wheel around which 

 the wire passes four or five times, running from this to the drum 

 of the storage reel — on which it is wound lightly and evenly by 

 automatic action. The wire comes in from and goes out to the 



