【正文】 and Wal es as wel l. Fi nal ly the Engl i sh government tri ed i n the earl y twenti eth century to form the Uni ted Ki ngdom by getti ng Irel and connected i n the sam e peaceful way. H owever, the southern part of Irel and was unwil li ng and broke away to form its own governm ent. So onl y N orthern Irel and joi ned wi th Engl and, Wal es and Scotl and to be e the Uni ted Ki ngdom and this was shown to the worl d i n a new fl ag cal ed the Uni on Jack. To their credi t the four countri es do work together i n som e areas(eg, the currency and i nternati onal rel ati ons), but they sti l have very di fferent i nsti tuti ons. For exam pl e, N orthern Irel and, England and Scotl and have di fferent educati onal and l egal system s as wel l as di ferent footbal team s for peti ti ons li ke the Worl d Cup! Engl and i s the largest of the four countri es, and for conveni ence i t i s di vi ded roughl y i nto three zones. The zone nearest France i s cal ed the South of Engl and, the m i ddl e zone i s cal l ed the Mi dlands and the one nearest to Scotl and i s known as the N orth. You fi nd m ost of the popul ati on settl ed i n the south, but m ost of the i ndustri al ci ti es i n the Mi dlands and the N orth of England. Al though, nati onwide, these citi es are not as l arge as those i n Chi na, they have worl dfam ous footbal l team s and som e of them even have two! It i s a pi ty that the i ndustri al ci ti es buil t i n the ni eenth century do not attract vi si tors. For hi stori cal archi tecture you have to go to ol der but sm al l er towns bui lt by the Romans. There you wil l find out m ore about Bri ti sh hi story and cul ture. The greatest hi storical treasure of al i s London wi th i ts m useum s, art col ecti ons, theatres, parks and buil di ngs. It i s the centre of nati onal governm ent and i ts admi ni strati on. It has the ol dest port buil t by the Rom ans i n the first century AD, the ol dest buil di ng begun by the Angl oSaxons i n the 106os and the ol dest castl e constructed by l ater N orm an rul ers i n 1066. There have been four sets of i nvaders of Engl and. The first invaders, the Rom ans, l eft thei r towns and roads. The second, the Angl oSaxon, l eft thei r l anguage and their government. The third, the Vi kings, influenced the vocabulary and pl acenames and sol ve thi s probl em . H e knew that chol era woul d never be control ed until i ts cause was found. H e becam e i nterested i n two theori es that possi bl y expl ained how chol era kil l ed peopl e. The fi rst suggested that chol era m ul ti pl i ed i n the air. A cl oud of dangerous gas fl oated around until i t found i ts vi ctim s. The second suggested that peopl e absorbed thi s di sease into their bodi es wi th thei r m eal s. From the stom ach the di sease qui ckl y attacked the body and soon the affected person di ed. John Snow suspected that the second theory was corect but he needed evi dence. So when another outbreak hi t London i n 1845, he was ready to begi n his enqui ry. As the disease spread qui ckly through poor nei ghborhoods, he began to gather i nform ati on. In two parti cul ar streets, the chol era outbreak was so severe that m ore than 500 peopl e di ed i n ten days. H e was determ i ned to fi nd out why. Fi rst he marked on a m ap the exact pl aces where al the dead peopl e had l i ved. Thi s gave him a val uabl e cl ue about the cause of the di sease. Many of the deaths were near the water pum p i n Broad Street (especi al y num bers 16, 37, 38 and 40) . H e al so noticed that som e houses (such as 20 and 21 Broad Street and 8 and 9 Cam bri dge Street) had had no deaths. H e had not foreseen thi s, so he m ade further i nvesti gati ons. H e di scovered that these people worked i n the pub at 7 Cam bri dge Street. They had been gi ven free beer and so had not drunk the water from the pum p. It seem ed that the water was to bl am e. Next, John Snow l ooked i nto the source of the water for these two streets. H e found that i t cam e from the ri ver pol l uted by the di rty water from London. He i mm edi atel y tol d the astoni shed peopl e i n Broad Street to remove the handl e from the pum p so that it coul d not be used. Soon afterwards the di sease sl owed down. H e had shown that chol era was spread by germ s and not i n a cl oud of gas. In another part of London, he found suporti ng evi dence from two other deaths that were li nked to the Broad Street outbreak. A wom an, who had m oved away from Broad Street, li ked the water from the pum p so m uch that she had i t deli vered to her house every day. Both she and her daughter di ed of chol era after dri nki ng the water. Wi th thi s extra evi dence John Snow was abl e to announce wi th certai nty that pol l uted water carried the vi rus. To prevent thi s from happeni ng agai n, John Snow suggested that the source of al the water suppli es be exam ined. The water pani es were i nstructed not to expose peopl e to pol uted water any m ore. Fi nal y “Ki ng Chol era” was defeated. COPERNICUS’ REVOLUTIONARY TH EORY N i col aus Coperni cus was fri ghtened and hi s m i nd was confused. Al though he had tried to ignore them , al hi s mathem atical cal culati ons l ed to the sam e concl usi on: that the earth was not the centre of the sol ar system. O nl y i f you put the sun there di d the m ovem ents of the other pl as i n the sky m ake sense. Yet he coul d not tel anyone about his theory as the powerful Chri sti an Church woul d have punished him for even sugesti ng such an i dea. They beli eved God had m ade the worl d and for that reason the earth was speci al and m ust be the centre of the sol ar system. The probl em arose because astronom ers had noti ced that som e pl as i n the sky seem ed to stop, m ove backward and then go forward in the loop. O thers appeared bri ghter at ti mes and l ess bri ght at others. This was very strang