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As the senior pupils were
studying the theory of navigation, Dr. Schmitz the headmaster of the
Royal High School decided to take them on a visit to the Royal
Observatory. Leaving the school shortly after the dinner break, led by
Dr. Schmitz, the boys made their way up the path leading to the top of
the Calton Hill. Surrounded by a high stone wall, the observatory, built
in the form of a cross with a dome in the centre, sat on the summit
directly across from the Nelson Monument.
Pushing open the front door, Dr. Schmitz led the boys up the path
leading to the building. The astronomer’s wife stood waiting in front of
the doorway to welcome them, her hand resting on one of the stone
pillars which supported the roof. "Good afternoon, Dr. Schmitz," Mrs.
Piazzi Smyth said. "You’ll have brought the boys to see the telescope.
Come away in! My husband is expecting you."
"Dr. Schmitz and the boys have arrived, Charles," the astronomer’s wife
announced, after leading them down the lobby to the observation room.
"As you know, they’re here to see the telescope and the machinery which
operates the time ball."
“A pleasure to meet you, boys,” the astronomer said. "I believe that
you’re here to find out how longitude is calculated. As you’re probably
aware, determining the correct time is absolutely essential. If a
navigator’s chart was a fraction of a degree out, the vessel would end
up miles off course. My assistant Mr. Wallace is just about to drop the
time ball. He’ll take you over to the monument! We’ll take a look at the
telescope when you return and I’ll demonstrate how we calculate the time
for the master clock."
As Mr. Wallace, Dr. Schmitz and the boys made their way over to the
Nelson Monument, the astronomer drew their attention to an insulated
wire running up the side of the tower. “Just before one, the master
clock in the observatory automatically sends a signal along that wire to
the locking pins holding the ball, releasing them, allowing the ball to
drop exactly on the hour.”
Climbing the stone steps
leading to the front door of the tower led by Mr. Wallace, Dr. Schmitz
and the boys went inside.
When they had nearly reached the top after the long climb up the narrow
circular stairway, the astronomer halted. “The room containing the
lifting machinery is very small. I’m afraid there’s only space for two
boys at a time," he explained to Dr. Schmitz. "Would you take the boys
out on to the observation platform?’’ he said pointing to a door. "The
magnificent view is well worth seeing. Send the boys up two at a time
when you’re ready, and I’ll demonstrate how the lifting machinery
works."
Pushing open the door, the boys took a look outside. The sun was shining
and the atmosphere was crystal clear. “Take a look at this, Alex!” one
of the boys said to his friend. “It’s like being up in an observation
balloon!” The boys could see the Queen’s Park, Arthur’s Seat, Salisbury
Crags and the Royal Mile stretching all the way from the Castle to
Holyroodhouse.
Leading his pupils round to the other side of the platform, Dr. Schmidt
pointed to the paddle steamers and sailing ships heading up and down the
Firth of Forth. “In a few minutes time, the ships’ captains will be
focusing their binoculars on the ball. When the ball drops they’ll set
their chronometers to the correct time. They may well have you bang in
their sights right now!”
Choosing two boys, Dr. Schmitz instructed them to go upstairs to the
machinery room. A square metal column bolted to the floor, running all
the way to the ceiling stood in the centre of the tiny room. Mr. Wallace
pointed to a metal plate. “Maudslay, Sons & Field, London, 1853. The
company set the time ball up," he explained. "They also designed the
lifting mechanism for the time ball at Greenwich.”
An electric bell suddenly started ringing. Mr. Wallace checked his
pocket watch. “Five to one! Time to raise the ball!” he announced, going
behind the column and turning the capstan wheel. “The ball is now
positioned halfway between the base of the mast and the crosspiece,” he
explained, removing his hands from the capstan wheel. “This sends the
signal to mariners out on the Firth of Forth and the people of the town
to prepare to set their chronometers, watches and clocks when the ball
drops at one.”
The sound of running water could be heard from inside the metal column.
“That’s the rain water draining from the roof,” Mr. Wallace added. “The
water running down the pipe cushions the ball when it slides down the
mast.”
Three minutes later, the bell rang and Mr. Wallace checked his pocket
watch. “Two minutes to one! Time to raise the ball again!” he announced,
turning the capstan wheel. “The ball is now positioned under the
crosspiece, ready for the drop!”
A fraction of a second before one, the boys heard the clicking sound of
the locking pins being released, followed by a swishing sound as the
huge black ball slid down the mast. The boys standing on the observation
platform cheered as the One o’clock Gun fired from the Half Moon Battery
at the Castle and the time ball dropped. “That’s it! Bob’s your uncle,
lads!” Mr. Wallace announced. “It’s now officially one o’clock! When you
go back downstairs ask Dr. Schmidt to send the next two boys up.”
"The boy with the black curly hair is extremely intelligent," Mr.
Wallace remarked to the headmaster after showing his pupils how the
lifting machinery worked. "He asked me a number of important questions
about the machinery. I wouldn’t be surprised if he turns out to be a
scientist, engineer or inventor in the not too distant future. What’s
his name?"
"I totally agree with your assessment of his abilities!" Dr. Schmitz
replied as he prepared to lead his pupils down the stone steps. "His
name is Alex. Alexander Graham Bell. He’s one of the Royal High School’s
brightest pupils!" |
