Road Making

John Loudnn McAdafn, acaordlitg to own account, eanic u Sootlaml trom America in 1 7i:ï, wben the Scotch Turhpike Acts bad been ftbötil tweniy vears in operation hikJ roatls ere still Deinst made everyuhere. He gut uppolntrd a Comiuiasiunur of Road, uiid alterward removed to Briitol, wbere be obtained ¦ sliiiilar oost and -ivas made a roatUtrete. Giften with a inania on the subject, be began iliimt 1704 to travel over ilic ooantry at liis own coat, and these labora he continued from Inverness to tlic Landa End tor s ¦x-aiul-iwvntj yai. tor no Ut her ptirpom, appitreutly, thsil to searcli lor u well-made road ud the btBt mean of nuiking oue. McAdam's plan of rnad-malttng iliffer¦d as much (rom tlie old way wliich bC t'ound In operation m a brulde does trom i ford. Instead oí going deep tor a "bottoining," hc worked tolely on the top. In itead it producinga peak, roof-like inass ofrough, soft rubblsh, hegota Sat,8tnooth nul soiid aurfaee. In lleu oí ¦ road fonr [eet and a half ihiough, he made ona of at uiost ten taches In tblckne&s, and for rocks and bouhh-r he rabetitnted stonea orokén small. Hb leudlng principie vu that ¦ rond [iiiL'bt to bu eonaidered aa M utiflclal flooring ao etrong and even as to el the licaviol vehlcle paM over t without iinpedime: t Theo peopto began to ieur witli wonder of ronde thirty and lorty fcet wide rising onlvthiee lidies in the center, and he propounded tlie extraordinary heresy that a bcttcr and more lastíi road could le made over the naked surface of a nioi'asi than over eolid rock. Another of hia easy lirst principies was that the uative soil was inore resistant wlien dry than wet, and that, as in realty it had to curry not alone the trafflc jut the rond also, it ougbt to be kept In i ¦onditKin of thegreatest reslstance; that the best way of keeping it dry was to put ov;'!1 ii a covering Imprevioua to ruin - tlie road, in fucl - and that the tbiekneat Bi ;his eovering to be regulated solely n relaiion to.it imperrioueueaa, and not at all as to its hearing of weights towhieb the uative soil was rjnite equal. Instead ot digiug a trcneli, ttimLre, i dq away with tlie SIM face of tlie uative soil, he csmfulky reapi caed h, and raittd lii- road sufflcieiitly above il to lel the water run olí'. Inipeimeability be ohtained by the practical dlscovery that atosea hroken small and (haken and pmaBflfl tcigether, as hy the uallic on a road, rapidly settled liwii face to face and angle to ungle, and made as clce a muse as a wall. Mankind 1U geneial DOW tielieve that thi last is uil tliat McAdam invelited; the rest is forgoiten. That Important fraotlon of bis jiscoveries is wbat has given to ns the verb to macadamize ("i pave a road with sinall brocen otoñe" - Skeat), and to tlie Frencli their noiin. macadam ("Nom d'uu pavage invente par un Anglais" - Littre). maeadamiêage and the verb macadamizer. If a man is knocked down by au omnibus lu tlie middte Ol the boulevard, a ParUian will now a days suy: "Je l'ai vu tomber sur le macadam." Surprise followed surprise. Koadswhich svere mere layers of' broken stone six, foar aud even as little as three inches in thlokneee, paased through the worst winters without Uieakinji up, white, as the coachmen used to say, "They ran true; the wbeel ran hard upon them, it ran upon the nail." (Jommis-ioners could not believe their cyes when they 8iw new roads made tor mucu less than il had cost theii) yearly to repuir their old ones. When an old road was yiven into McAdam's charge he oflen made a new one of it tor eigaty-eight pounda a mlle,while arouud Loudon the cost ot annual repairs had been tour hiuulred and seventy pouuds a niile. For he kneu that the roads - web had been the Ignorant waste - geuerally coniaintd niatcii.d enough for their use lor several years it properly applied. Unless the road uas hopeless, he weut to work in a practical, cbeap way; lirst cultlng off the "gridirou" of ruis ín tlie ceuter "to a level with the bottom of the furrows," then "picklng" the road up to a depth of foui inches, removlng all the chalk, clay or mud, breakiiiif the large atonaa small, and almply putting them bck a'ain, and oue of his direct. ons to bis worknien was that "nothing is to be luid on the clean slmie ou pretence of bindinj;." Bilt tOO oiteil the road was so bad, as at Ëgham, that it Bad to he leuiovtd to its tonndations. For the repairs of lus roads, when once made, he always cho.-c wet weatuer, and "lOOtened the hardeued surtace with a piek" bfifore putting on the Irer-h broken stone; tbingi familuu enough to us now, bot paradoxe! theii to all the confrateruities of the roads. In this way he had the greatest success with the tree.-ri.ne near Balli, and on a road out of Bristol toward Old Down, where everyboily had ahvayssaid a gaod rond liever wuuld be made with the malcriáis ivailable. Thii ïmpnssible road of eleven miles, which the PoBtmaater General, as a lat re.-ource wasaboutto Indlct, he perfeeted In tw months In 181(i tor lifty-tive pouuds a uiile. Indeed, as to material, they were to sorae extent a matter of indlfference to him, provided tbeywere stones and stoues only. Flint (Essex and Sussex), hc said, made an excellent road if only broken properly small; liniustoiie (.Wllta, Bomerset and Gloucester) cou-oiidates aoonest of all. but is not the oaoat lastlngj the pebbles ot Büropahlre and Btaffordahln were also good, and the beach pebbles ol Essex, Kent and Susex were soine of tbc best materials in the kindom; but the whinstoue or granlte of the North and of Scotlaiid he prououooed the most durable. Even in the breuking of stones McAdam made il rcvoliition. He law tlial alilebodied men standing up with heavj hammen waated the greater portion of th'ir atrengtb. He made hls breakers Bit, no that all the force of tlie blows took direct effect on the f tone, and the rcsult was that he found small haininers did the work perfectly well, and thus was enabled loconliiKi it to old men past hard labor, womcnl aud boy, wklcli rcdukU the coat of the broken 8tone by one-half. The si.e to wbich tlie stone should be broken hedutermined in a practical way liy (lie area of contact of :m ordinary whoel with a smooth road. This hefound to beaboutan inch lengthwise, and therefore he laid it down that "a stone wliirh exceedi an inch in any of its diraensions is mischievous;" that is to say, that the wheel in pressinpr on one end of it tends to lift the oth:r end out of the road. In practice he found it siuiplest to fix a weleht of six ounces, and iiia suivevors carrled about scales to test the largest stones In each heap. He would allow no largo stones even for the foundation of liis rond, for he found they constan tly worked upward by the vibratiou and preMure of the tiafflc. The whole road wh8 grnall broken stone, even over