January 1, 1887.] 



♦ KNOW^LEDGE ♦ 



55 



Not only does the roof crush down, but the floor bends 

 upwards, owing to the transmission of the pressure of the 

 superincumbent rocks in all directions — that transmission 

 of pressure which constitutes the essential characteristic of 

 fluids. This occurs more or less everywhere, and in old 

 abandoned deep workings the roof and the floor ultimately 

 meet, unless the air or water confined between them is 

 unable to escape. Great permanent subterranean cavities 

 at considerable depths are, I maintain, impossible. As will 

 be seen presently, when I come to the methods of working 

 out the coal, this impossibility has caused us to leave behind 

 hundreds of millions of tons of good coal in our old mines, 

 to be hopelessly buried beyond human reach. 



Five to ten feet is the ordinary width of main roads or 

 way-gates. Even this moderate width requires artificial 

 support by means of poles or logs of oak or larch, commonly 

 grown for the purpose in mining districts. These are cut 

 to lengths respectively corresponding to the height and 

 width of the road, two to height for each ore for width. 

 They vary from four to eight or ten inches in thickness. 

 The two that are as long as the height are placed u]5right 

 against the walls opposite to each other ; the one matching 

 the width of the road is laid across these as a cap or head- 

 piece. This is continued at intervals of three or four feet in 

 ordinary rock, but when the roof is friable, i.e., liable to 

 crack off in scales as the down-bending proceeds, it is 

 further protected by planks laid from one cap-piece to the 

 other. The expense of this timbering is a serious item in 

 ordinary colliery operations. 



In some cases the main roads ai'e arched with brick or 

 stone, like railway tunnels, and even built with an invert 

 arch below to prevent the rising of the floor. 



If the creeping or yielding to pressure wei'esuch as occurs 

 when homogeneous material, such as metal, is thus forced 

 to yield, no serious mischief would result ; a mere bulging 

 might be tempor.arily remedied by i-enewed excavation, but 

 the structure of coal and the other rocks of the coal measures 

 being either laminated or stratified, the bending produces 

 superficial disintegration or chipping off in flakes, which too 

 often are of sufEcient magnitude to maim, and even crush to 

 death, the man who is working below. 



Outsiders hear of the wholesale catastro])hes where by 

 explosion of firedamp, or by the wrecking of a shaft, or by 

 the breaking into water accumulated in old neighbouring 

 workings, &c., man}' men are killed at once ; but the far 

 more serious danger to the coal-miner than any or all of 

 these, that of falling roof, is rarely heard of beyond the 

 immediate neighbourhood of the pits. The reason is simply 

 that killing and wounding from this latter cause happens to 

 only one man at the time. But the sum total of these 

 isolated aises, as shown by general statistics, tells a diflerent 

 tale from that of occasional newspaper reports. 



In 1883 the loss of life from explosions in coal mines 

 amounted to 134; deaths in shafts, 97; at surface, 108; 

 miscellaneous underground, 2-lG ; falls of roof and coal, 

 469 — total, 1,054. Thus in this year fiiUs of roof and 

 coal killed three and a half times as many as explosions. In 

 certain years, when one or two great explosions have 

 occurred, the numbers killed by explosions reach or exceed 

 those killed by falling roof, but generally speaking the 

 fatalities from falling roofs amount to about double the 

 number due to explosions. The numbers wounded, in 

 many cases permanently crippled, by falling roofs is far 

 greater than those killed, as may be readily supposed. Of 

 these we hear little or nothing. It is not in the main roads, 

 but in the side workings or " bord gatts " where most of 

 these sad accidents occur. Usually an explosion kills its 

 victims with little or no suflfering, the carbonic acid and 

 carbonic oxide instantly resulting from the explosion are 



an;esthetic in their action, and produce nearh' painless 

 suflbcation. The crushing accidents are of a peculiarly 

 painful chai'acter. 



EVOLUTION OF LANGUAGE. 



By Ada S. Bali.ix. 



ROOTS AND THEIR DEVELOPMENT. 



CCUSTOaiED as we are to the use of lan- 

 guage in its present highlj- developed state, 

 with all its complications, it becomes 

 somewhat difficult for us to conceive a kind 

 of language constructed of roots — words 

 such as I described in my last ; but such a 

 conception is aided by observing how 

 diflerent languages run, as it were, on 

 diverging lines, so that it may be possible, beginning, 

 metaphorically speaking, at the most divergent points, to 

 trace them up to the point of juncture. " Long before 

 the age of Aryan separation the several relations in which 

 a word might stand in a sentence had been clearly evolved, 

 and certain terminations had been adopted and set apart to 

 denote these relations. The creative epoch had passed, and 

 the cases and numbers of the noun had entered on their 

 period of decay. But with the verb it was quite otherwise. 

 Here we can ascend to a time when, as yet, the Aryan verb 

 did not exist — when, in fiict, the primitive Aryan conception 

 of a sentence was the same as that of the modern Dayak. 

 Most verbs presujtpose a noun, that is to say, their stems 

 are identical with those of nouns."* For example, the 

 Sanscrit hhardvi-mi, Greek tit/te-mi, originally meant 

 •• bearing of me." '■ placing of me." 



While the Ai-yan verb can thus be traced to a nominal 

 form, the Semitic verb was originally, and still remains, a 

 noun, whatever tenses and moods it has gained being of 

 comparatively late origin, and expressing not time but rela- 

 tion, whereas the Aryan verb from the fir.st moment of its 

 existence expressed time. In Hebrew, for example, which 

 may be taken as a type of Semitic tongues, the root, pure 

 and simple, is used to denote the third person singular of 

 the perfect, and the other persons are obtained by attaching 

 atfixes. The two so-called tenses, perfect and imperfect, are 

 used interchangeably to express either past, present, or 

 future. Thus Hebrew is a specimen of language composed 

 of nouns. To take an opposite example, in Algonquin 

 everything tends to verbal expre.'-sion ; adverbs and pre- 

 positions are regularly conjugated, and nouns are to a great 

 extent verbal forms — for example, house is "where they 

 live." The tendency of this language is to very long words, 

 the longest in Elliott's Massachusetts Bible containing 

 thirty-one letters and eleven syllables. It is icitf-appfisitu- 

 rjussun-7ioovjeht-unk cjuoh,\iteva.\\j, "he came to a state of 

 rest upon his bended knees, doing reverence to him." — (J. H. 

 Trumbull). The mere contemplation of it is overpowering, 

 and we turn with relief to apparently simpler cases. 



The Eastern division of Polynesian languages, which have 

 alphabets containing not mor^ than ten, and often as few as 

 seven, consonants, their syllables being all open, composed of 

 single vowels or of a vowel preceded by a single consonant, 

 are polysyllabic, but have no inflections, expressing neither 

 gender, number, place, mode, nor person. Their- words are 

 impartially used without any change, as verb, substantive, 

 adjective, and even preposition. Their grammar is made 

 up of pronouns, indicative participles, prepositions, and the 

 like, and they possess nothing which can properly be called 

 a verb. In this we approach to the Chinese type of language, 



* Sayce, " Introd. Sc. of Lang.," vol. ii., p. 150. See what follows. 



