26 



KNOWLEDGE ♦ 



[Nov 1, 1885. 



(from a draper's, if unable to obtain them more easily) 

 two wooden rollers, five to six inches in length and two 

 inches or thereabouts in diameter. Round off the 

 ends of one of these pieces and plane it down 

 longitudinally, so as to form a flat face, and cover 

 this loosely with a piece of soft leather, filling it 

 out with a quantity of horsehair (or other convenient 

 material) to form a pad. Along one edge of the pad sew 

 a piece of silk four and a half inches long and an inch 

 and a half wide, and along the other edge another 

 piece of silk about the same width but about four 

 inches long. The short piece forms the actual rubber, 

 and the long piece the flap which rests on the upper 

 half of the cylinder. On the under side of the roller 

 (nearest where the silk rubber is attached) bore a 

 hole, half an inch in diameter, and an inch or so deep, 

 and fix in it a piece of half- inch glass rod about four 

 inches long. Next, with the aid of a little flour 

 paste, cover the remainder of the roller evenly with 

 tin-foil. Let the free end of the glass rod be inserted 

 in a half- inch hole bored in another piece of wood. 

 The latter piece is shown in section in Fig. 6. In the 

 tipper portion, C D, which may be round or square, the 

 hole A is bored, and the glass rod fitted. The lower 

 portion, B, should be a quarter of an inch thick, an inch 

 wide, and an inch long. Through the centre a hole, a 

 quarter of an inch in diameter, should be bored. This 

 tongue should fit, and work betweeit the similar tongues, 

 B C, in another piece of wood (illustrated in Fig. 5), 

 which also measure a quarter of an inch thick, by an 

 inch long, and an inch wide. Quarter-inch holes being 

 bored through them, a solid pin, an inch long and a 

 quarter of an inch in diameter, should be passed throttgh 

 the three holes, the result being that the glass rod can be 

 worked to and fro at 2:ileasure. The combination is shown 

 sectionally in Fig. 4, where A B is a portion of the base, C 

 thecombinatiim of tongues, the lower portionof the bottom 

 piece of wood being screwed to the base from the under 

 side. The plane of motion of the rod G should be at 

 right angles with the spindle, so that the rubber which 

 surmounts the rod may be moved to or from the cylinder. 

 A small pulley (P, Fig. 4), sa,j, an inch in diameter, is 

 fixed by means of a piece of wood or stout wire, "W, to 

 a convenient part of the base (itnder the cylinder), and a 

 half of a cotton-reel, R, is screwed on to the base between 

 the pulley and C. Apiece of stout silk-thread, S, is then 

 tied round the glass rod, passed over the pulley, round 

 the reel, and secured in a notch in the rim of the latter. 

 The object of this arrangement is to aiford facilities for 

 adjusting the pressure of the rubber against the glass as 

 it revolves. This object can also be attained by in- 

 creasiag the length of the glass rod and attaching the 

 upper part of the collar (C D, Fig. 6) to the base by 

 means of a hinge. The position of the hinge will be 

 apparent. Either of these plans will be found preferable 

 to the ordinary method of screwing the rubber forward 

 from the top of the glass rod. 



All that now remains to be provided is that part 

 known as the prime conductor. For this, tise the wooden 

 roller above referred to, rounding off the ends so as to 

 remove any sharp edges or points. Then bore in the 

 middle of its length a hole half an inch in diameter and 

 about an inch deep, fitting into a piece of half-inch glass 

 rod about six inches long. The lower end of the rod 

 should be fitted iato another piece of wood screwed on to 

 the base. The side of the roller nearest the glass should 

 be furnished with a row of points, obtainable by cutting 

 the heads off a niimber of pins and pushing them into the 

 wood. The height of the prime conductor should be 



such that the pin-points are on the same level as the 

 spindle. 



The glass rods sujiporting the rubber and the prime 

 conductor should be coated with a thin layer of shellac 

 varnish, to prevent the electricity escaping. 



In mj- next I shall deal with the question of working 

 the machine, and shall detail a number of interesting 

 experiments that can be worked with it. 



THE ORIGIN OF LANGUAGE, 

 By Apa S. Ballin. 



HATE said in my essays on " Thought and 

 Language " that the three chief theories of 

 the origin of language are by no means so 

 opposite as is generally sujjposed, but that it 

 is quite possible that all are equ.ally true. 

 In point of fact, in the preceding series of 

 articles, I have really set out a theory which 

 includes them all, by demonstrating — 1, the influence of 

 emotional signs as a part of language (which forms the 

 basis of interjectional theory) ; 2, the necessity of a system 

 of signs as a means of communication (which, if I cor- 

 rectly interpret Prof. Max Miiller's theory by saying that 

 he maintains that man speaks of necessity just as a stone 

 rings when struck with iron, is simply another way of 

 stating that language is a response to a certain stimulus, 

 one means of adapting man to his environment) ; 3, and 

 lastly, how a purely imitative language, such as that of 

 the deaf and dumb, may be naturally developed. 



The great question which so exercised the minds of the 

 ancients, as to why certain sounds (words) were first used 

 to express certain things or ideas, is to a great extent 

 answered by the theory of the natural origin of language, 

 which I am in these articles endeavouring to explain. I 

 believe that just as the origin of thought may be traced 

 back to sensation, so the origin of language may be found 

 in the outward manifestation of the same — in involuntary 

 expressive gestures and sounds, and that these, being 

 found useful, were voluntarily repeated as a means of 

 communication. In co-o])eration with this purposive 

 element was the imitative tendency, which I have shown 

 to be so highly developed in those at a low stage of intel- 

 lect. Thus emotional and imitative sounds become part 

 of a system of communication, assisted, as we now find 

 it among savages, by the natural sign-language, and it is 

 also probable that certain sounds, originally uttered at 

 random, in spontaneous exercise of the vocal organs, as 

 among young children, were also aflixed by convention to 

 things and ideas with which they had no other relation. 



It maj- be said that man having accidentally found 

 that good resulted from his having given out some 

 emotional sound or gesture, voluntarily repeats the sound 

 or gesture as a means of communicating with his fellows. 

 Having thus voltintarily imitated himself and found it 

 useful to do so, he goes a step further and proceeds to 

 imitate nature for a similar ])urpose, and as an aid to 

 self-preservation. Thus it is that after all, the imitative 

 faculties are the most important in the production of 

 language, and this truth was evidently appreciated by 

 Plato,* who puts into the mouth of Socrates the opinion 

 that all names, whether primary or secondarj-, are in- 

 tended to show the nature of things ; and that the 

 secondary derive their meaning from the primary. 

 But how, he queries, do the primary names indicate 

 anything ? And then he asks the further trenchant 



♦ " Dialogue Cratvlus," 



