at the age of 22 john harrison built his 1st chronometer he spent 60 years of his life studying how time could be measured precisely his premise was that if a navigator at sea knew the exact time in his home port then from the difference between that time and the time on board ship he could calculate the position of the vessel in degrees latitude and long it cheap. for centuries no one had been able to make a clock that measured the time accurately at sea without being influenced by fluctuations in temperature by humidity or by the ship's motion and that was john harrison's great achievement. the h 4 is the size of a pocket watch and it represents the sum of harrison's skills on a 12 week trial voyage in 761 this little chronometer deviated from greenwich mean time by only 5 seconds. in 884 an international conference was held in washington d.c. at which 41 delegates from 25 nations agreed to be clad the line of long beach you don't which greenwich late as the prime meridian in doing so they merely confirmed what had long become standard nautical practice because once harrison's met

my name is james harrison i work. this week john world stories. syria surviving in. kenya battling the sand mafia. but we start off in hong kong where hundreds of thousands of people are demonstrating against a proposed extradition girl among them many students there protesting against beijing's growing influence. school's out for 17 year old zach today it's the final exams weekend on kong and zach is completing grade 11 but his mind is not with the exams these days. today i get my chinese language tested and i think i did quite ok. for the other topics that require more preparation things aren't looking that great this year but i'm setting aside my. i future for the future of hong kong. zack is an organizer for a group of middle school students in hong kong's protest movement they are planning to meet this afternoon but suddenly he gets a call from a friend who thinks he's followed by the police case that's what you'll let me call you later. i have to. decide to hold the meeting but won't have that friend join in. the government's announcement to delay the bill is a

that night i booked ringo starr, paul mccartney, john lennon and george harrison for $3,000. >> for themre a bunch of guys from liverpool. people in london would have looked down on liverpool back then, but liverpool was a poor town. poor towns become places where all sorts of contraband gets exchanged, and one of them at that point was great music. >> a lot of the sailors and people coming back from america were bringing back these records. some were pop records, some were called race records because they were by black artists. ♪ ♪ >> the level of influence that american rock and roll, blues, country and western, motown had on those kids growing up in england was really amazing. ♪ ♪ >> so i would listen to buddy holly, all the great rock and rollers. >> it was like a new language for us. >> the power of the jukebox, there's nothing quite like it. ♪ my dream came true ♪ >> the beatles took a bunch of those strains, the everly brothers in the '50s was a big influence for them with the harm niezgoda. ♪ wake up, little susie, wake up ♪ ♪ wake up, little susie, wake up snooi ♪ ♪ >> so the be

two of them were from the county i grew up in virginia, john tyler and william henry harrison were fromed. virginia is a cool place. it's the birth of the nation right there. >> he can go on forever. >> could. so we'll turn our attention to something else. >> thank you, spencer. >> new developments in the screen age. are we starting to develop horns? >> what. >> i know. some scientists say we are. we'll explain. >> i'm 7 on your side michael ♪ ♪ this is how driving should feel. the tech-advanced nissan leaf. the best selling electric vehicle of all time. this is nissan intelligent mobility. ♪ cannabis sales rising across the globe in part because of canada's legalization of marijuana. the state of legal cannabis markets report was released today and it estimates the world's market could hit $159 billion this year. that would be up 36% from last year. that includes cbd products, medical marijuana, recreational marijuana and hemp. >> apple announced a voluntary recall of certain mac book pro laptops today. >> michael finney has the details and how to get it fixed. a little scary. >> it is

harrison sat down with her a couple years ago. take a listen. intern sensation? >> for what reason? >> because of what you did. >> johnke a trip without you saying it was okay. >> yeah, he was -- he was like me. he didn't trust the -- they put everyt in the computers. >> rep the street :00 live in southwest, aimee cho, montgo county this morning, family community activists are fighting for justice for robert white a year after >> we've got to always try to love. >> he had a lht within him and when i heard things, it was >> white was shot and killed montgo county police officer last year. he was unarmed. the silver springs justice family and friends said white had mental illness and the situat should have been incide of racial profiling. it's not isolated. we have a problem with our policeofficers. >> the officer was clred of the coalition wants better with mental health issues. new details this morning in the montgo county pncsecutors ae again asking the judge to grant an independent mental she's accused of murdering her they have never been found and arfor th past five ye she's trial by doctors with the state psychi

and thank you for soon sending jamie harrison to the senat of the united states of america. jim: thank you very much, john. many of you recall, john was here last year. thank you so much for coming back. ladies and gentlemen, our next candidate is someone with whom i've partnered in recent weeks to do what we can, to redules student debt. she's got a plan for that. and i want to share in that plan. ladies and gentlemen, elizabeth warren. cheers and applause] >> hello, south carolina! -- we -- we got a government -- we got a government that works great! it works fabulously! it works terrifically for the rich and the powerful! i'm running for president because i want a government that works for the rest of us. i'm in this fight because i believe that the time for small ideas is over. we need big, structural change in this country and this economy. and big structural change starts with big ideas. how about a wealth tax on the 1%?.10 of and, you know, what we can do with that money? we can build opportunity in this country. universal childcare for every baby age 0 to 5. pre-k for every 3 year-old and 4-year-o