Farrow's military encyclopedia : a dictionary of military knowledge . y movement of the shaft afterwards re-moves them altogether, or makes them bear equallyand at the same time on the surface designed to re-ceive the registry. By what precedes, we see thatthe property of connecting automatically can be giv-en to a register only on the important conditionof limiting tlie course of the pen and in alsoreducing the counteracting force which determinesthe rapidity of its movement of disconnection; themagnetic attraction, exerted on the armature, dimin-ishing according to the square of the distance
Farrow's military encyclopedia : a dictionary of military knowledge . y movement of the shaft afterwards re-moves them altogether, or makes them bear equallyand at the same time on the surface designed to re-ceive the registry. By what precedes, we see thatthe property of connecting automatically can be giv-en to a register only on the important conditionof limiting tlie course of the pen and in alsoreducing the counteracting force which determinesthe rapidity of its movement of disconnection; themagnetic attraction, exerted on the armature, dimin-ishing according to the square of the distance, weimagine that, in practice, in order to preserve a coursesufficiently rapid, we may be led to reduce, to a verysmall quantity, the amplitude of the displacement ofthe pen, which renders the readings difficult. A rem-edy was sought for tliis defect by the employmentof organs for multiplying the movement like thoserepresented by Fig. 3. Mr. Napoli also constructedregisterssuch as that represented by Fig. 5. in whichthe amplification of the movement was produced by. the medium of two cams resting one on tlie other,with surfaces arranged in such a manner as to vary,at each instant, according to a proper law, the rela-tion of the arms of the lever and consequently theaction of the counteracting spring acting then direct-ly on the shaft which contains the pen; this is the,arrangement known by the name of distributer ofUobert Iloudin. Mr. Marcel-Deprez also soughtto overcome this difiiculty by using electro-magnets,comliiued in i)airs and of dilTerent forces, workingsuccessively liy the .same action of the disconnection;the attraction of the armature, in ordinary circum-stances, was produced by a very small ••ind very sen-sitive electro-magnet, whose retardation of disconnec-tion could be made small, and, at this lime of the dis-coniieilion. the armature established contact whichintroduced in the circuit a larger electro-magnet sus-ceptible of acting with force on the armature
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Keywords: ., bookcentury1800, bookdecade188, booksubjectmilitaryartandscience
