Correspondence

1869 Scientific American  
IlnprOVeluent in Straw-Cutting llIacl1ines. The accompanying engravings represent in section the parts of a new style of machine designed for cutting straw and hay for the feeding of stock. Instead of rotary knives the edges of which meet each other and thus sever the straw, or one ro tating cutter bearing on a yielding roller,or even a reciprocat ing knife passing by a fi xed knife, this machine has two re ciprocating cutters, each moving in opposite directions simul taneously, and so set as
more » ... ly, and so set as to cut like shears and with a drawing motion. The feeding of the material is also automatic , thus obviating the danger of severed or lacerated fi ngers . The machine is quite simple in construction , and, as seen from the foregoing statement, easy and exact in operation. Fig . 1 is a vertical longitudinal section; Fig. 2, a transverse vertical section; and Fig. 3 , a view of the knife and hand lever. The two front uprights are double grooved to receive the lightning rods mounted , and six barns out of ten were burned to the ground with lightning rods mounted; that is , ten barns burned up, six of which were provided with rods and four had none. About that time a large number of buildings in New York and Boston suffered from electrical explosions, al though surmounted by rods , and it was these stubborn facts that induced me to give to a widely published paper the sci ence and facts in the case. The only counter article on the subject that I learned of was from Mr. Quimby, who simply stated that the cases I made reference to "were not surmount ed with rods of his construction!" Now for the facts of the science . The discharge generally comes from the cloud to the earth. When it passes within tractive distance of a trac tor , which may be a lightning rod or other metallic promi nence , or any projecting pointed wood or stone , it will fiy to that, at an angle to its previous course . \"{hen in such case lightning rods down from two houses I owned , looking upon them as decoy ducks to the errant thunderbolts that might chance to happen in that direction. A lightning rod , or protector from lightning , either from a pending surcharged cloud, or a bolt, to be efficient , should be elevated on a mast or pole as high as poesible-better 150 fElet high than 75 feet-and it ought to stand a little distance from the building or buildings , surmounted with a metallic ball and finely-pointed gold or platinum point; it will then silent ly draw off the surcharge from a proximate cloud, and will also draw a stray bolt to the ball and rod, that may be mov ing in the direction of the building . By bolt or thunderbolt tlteintelligent reader will understand me to mean electrical explosions, in distinction from surcharges or surcharged cloud. A bolt is exploded electricity; that is to say , the can non ball shot out of Jupiter's gun: surcharges or surcharged AMBRUN'S PATENT DOUBLE ACTING STRAW CUTTER. fr ames that carry the knives. These are fixed rigidly, at op-it strikes the lightning rod it is like trying to knock the dis-cloud is the cannon ball lying quietly within the cavity of posite angles , in their frames. Each of these frames has on charged cannon ball away from your person with the bayonet Jupiter's cannon , but ready to go off at any moment that the its inner surface a toothed rack , as seen in Fig . 1 , the teeth of of your musket instead of drawing the charge from the can-match of electrical traction comes within its reach. which mesh with those of a pinion , thus insuring simultan-non with the screw-rammer, or plugging up the prime-hole As regards the interruption of conduction by paints or other eous reciprocatin g motion to the knives , seen plainly in Figs. with a rat-tail file. substances on the surface of a rod , I would say that I have
doi:10.1038/scientificamerican02061869-85 fatcat:3bovby5ftbdcbj5fhpdbvnd6ie