Kirkpatrick Macmillan.

[neptune]

I have just been reading about Kirkpatrick Macmillan, who some believe built the first rear wheel drive bicycle. It was propelled by treadles which moved back and forth, rather than a rotary movement. The gear ratio is 1:1 , and we are told that he often rode to Dumfries, a distance of 14 miles in " less than an hour". So let us call his speed 14MPH.
We are told that the front wheel was 30 inches diameter, and the rear driving wheel was 40 inches diameter. The circumference of the rear wheel is 30 x 3.142 =94.26 inches, or 7.855 feet.

One mile is 5280 feet. so for every mile we get 672.1833 "Revolutions" of the treadles.


At 14 MPH each mile takes 60 minutes divided by 14 = 4.285 minute

So in one minute the treadles "revolve" 672.1833 divided by 4.285 =156.8 times.

Remember this guy is a blacksmith, not a longtime experienced cyclist. An he can attain a cadence of 156.8 .

Something does not add up here.

 

[Old_Dave]

Never under estimate the super powers of a blacksmith

But maybe the ride was downhill, lol


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[billadie]

We are told that the front wheel was 30 inches diameter, and the rear driving wheel was 40 inches diameter. The circumference of the rear wheel is 30 x 3.142 =94.26 inches, or 7.855 feet.

Er, isn't the circumference 40 x 3.142 = 125.66" or 10.47 feet?

 

[Old_Dave]

Pi r squared

R = radius wot is 1/2 of the diameter
40" driving wheel
125.66370614359172" , lol

Billadie can do sums


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[neptune]

@Billadie. Well spotted. So let us try again. Circumference of drive wheel is 10.47 feet.

So every mile, the wheel revolves 5280 divided by 10.47 =504.29 times . A mile takes 4.285 minutes.
so revs/ min is 504.29 divided by 4.285 =117.687.

That sounds a lot more reasonable.

 

[flecc]

Still an exceptionally high cadence though, and especially so for treadles where the leg masses have to reverse direction rather than rotate around an arc. Very unlikely and I think it's a fair bet that the statement "under one hour" is an exaggeration, not unusual at that time. That was an era when a bottle of patent medicine was commonly said to cure anything from a cough to cancer and gross exaggeration about progress was almost the norm.

 

[neptune]

My first reaction was that he had found a short cut! Until the coming of the railways, there was no such thing as standard time. It is quite likely that most people did not have a clock in the house, and watches were out of reach of the working class. If you lived in a town or village, there was of course the church clock, which as well as giving a visual indication, would strike the hours and sometimes the half and quarter hours as well. I often wonder though how men in remote rural areas managed to get up on time at 4 a.m. to feed the horses ready for starting work at 7 0`clock.
Time and speed aside, we still have to respect his ability. He rode the 68 miles to Glasgow, in two days. Remember his bike probably weighs a hundredweight [112 pounds]. He has a fixed gear ratio, and the west coast of Scotland is not known for its flat roads. Nor are we talking about smooth tarmac, but probably rutted cart tracks. He did however have puncture proof tyres.
In Glasgow, he had an accident, knocking down a little girl. She was not badly hurt, but he was prosecuted and fined "Five British shillings." It is rumoured that the Magistrate slipped him the money to pay the fine.

 

[flecc]

Time and speed aside, we still have to respect his ability. He rode the 68 miles to Glasgow, in two days. Remember his bike probably weighs a hundredweight [112 pounds]. He has a fixed gear ratio, and the west coast of Scotland is not known for its flat roads. Nor are we talking about smooth tarmac, but probably rutted cart tracks. He did however have puncture proof tyres.
In Glasgow, he had an accident, knocking down a little girl. She was not badly hurt, but he was prosecuted and fined "Five British shillings."

That sounds much more likely for a blacksmith, a feat of strength and endurance rather than athletic speed. He'd probably have broken a modern bike within the first few minutes with his strength and those conditions.

Accidents with the first vehicles were amazingly prevalent. Stephenson's Rocket hauled train killed a man on the track at it's first demonstration and one of the first motor cars seen in Britain killed a woman when it was being demonstrated at Crystal Palace, making her the world's first car accident death. I suspect unfamiliarity made people unaware of the potential dangers.

 

[john h]

kirkpatric macmillan was not a blacksmith his family owned courthill smithy 'altho he was brought up there he worked at the vulcan foundery in glasgow 1840 he built his bike in1839 with metal rims ,must have been some feat to pedal on the cobble streets of glasgow ; the accdent happend 1842.