1
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[Door opens, footsteps]

2
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[Creak!] [THUD!]

3
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[Jazzy music: 'The Russians Are Coming' - Val Bennett]
[vaccum cleaner noise]

4
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[Jazzy music: 'The Russians Are Coming' - Val Bennett]
[TV static noise]

5
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[Jazzy music: 'The Russians Are Coming' - Val Bennett]
[Steam hisses]

6
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[Jazzy music: 'The Russians Are Coming' - Val Bennett]

7
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[Jazzy music: 'The Russians Are Coming' - Val Bennett]
[sewing machine rattles]

8
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[Jazzy music: 'The Russians Are Coming' - Val Bennett]
[*Whoop!*]

9
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[Jazzy music: 'The Russians Are Coming' - Val Bennett]

10
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[Noise of vacuum cleaner]

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Tim: The modern vacuum cleaner is a wonderful contraption.

12
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It's really quite magical the way it make dirt vanish from completely inaccessible places

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And before it was invented houses were just much much dirtier places.

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More like my workshop...

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Though even my workshop isn't usually quite as dirty as this!

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It may be a myth that vacuum cleaners are labour saving devices.

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It's said that people spend just as long cleaning their houses today as they did a hundred years ago.

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But these machines certainly have made houses cleaner!

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Well in this programme I hope to look at exactly how vacuum cleaners work and how they evolved

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[Birds tweeting]

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Without vacuum cleaners the only way to clean carpets and upholstery was to take them outside and beat them

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An activity that was traditionally performed just once a year.  The spring clean.

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There was considerable incentive to invent a cleaning machine.

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Particularly because Victorian houses were so cluttered and full of soft furnishings

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Numerous patents for sweeping and beating machines were taken out from the 1850s onwards

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and some of these did include primitive suction devices.

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[Engine noise]

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But the practical vacuum cleaner had to wait for the arrival of reasonably small and efficient power sources.

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By 1900 the first internal combustion engines had appeared

30
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and amongst other things they were used to power compressors to generate compressed air.

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[Compressed air]

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Several Edwardians experimented with cleaning carpets and upholstery with compressed air

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but the problem was that the dust just went everywhere.

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And then settled back down exactly where it had come from.

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A demonstration of this rather inadequate cleaning system, on cleaning railway carriages

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in St. Pancras station, in 1901, was witnessed by an engineer called Herbert Cecil Booth.

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Booth was a civil engineer who designed bridges and the enormous big wheels popular at the turn of the century.

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This one was put up in Blackpool in 1896

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It seemed obvious to Booth that sucking the dirt into a container through a filter would be a more sensible idea.

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And his very first experiment: holding a hankie over a sofa and sucking hard through it

41
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left the hankie filthy. And proved the principle to himself.

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His first machine was simply a cloth bag to collect the dirt and a suction pump.

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It worked well but it was very large so it had to be parked outside customers houses.

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[boing]

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It became known as the noisy serpent, and he was frequently sued for frightening passing horses.

46
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[Horse neighs] [Screech] [Boing]

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The success of Booth's machine was largely due to the coronation of Edward VII in 1902.

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Woman: Oh! Dust! There's dust on the....

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Tim: In all the preparations it hadn't been noticed until the last minute

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that the carpets under the throne in Westminister Abbey were filthy.

51
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Booth's machine was the only effective way of cleaning the carpet without removing it.

52
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Man: We'll vacuum you too. Oops!

53
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[Wheels rattling]

54
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Tim: The king later heard of this and ordered a demonstration at Buckingham Palace, buying two machines.

55
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King Edward: Your appawatus is fwightfully impwessive!

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Booth: Oh thank you very much sir, thank you very much. Ho Ho!

57
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Tim: Booth added clear inspection tubes so people could watch the dirt being sucked in

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And the machines became prime attractions at fashionable soirees.

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With royal patronage the success of the machine was assured

60
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Man: A most marvellous modern invention!

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Booth's machine caught the public imagination but was much too large and cumersome for most homes.

62
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So various other manufacturers started introducing much smaller hand powered machines.

63
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This one's the sweepervac. Made in San Fransisco.

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The British Queen

65
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it doesn't seem to be doing very much this one. A bit difficult to use too.

66
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The star.  This one feels more comfortable.

67
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just swept up a feather.

68
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And, er, what's this one called?  The Reeves pneumatic broom.

69
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...doesn't sweep very much up at a time

70
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nearly got that bit of dirt, no.

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Most of these machines would have been considerably less effective than a simple dustpan and brush.

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But at the time there was a phobia against dust which was believed to be full of germs.

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A French doctor in 1907 wrote "Dry sweeping and dusting are homicidal practices

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they consist of taking dirt which has been lying on the floor and on the furniture

75
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mixing it with the atmosphere and causing it to be inhaled by members of the household.

76
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In reality it would be infinitely preferable to leave the dust alone where it was."

77
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Well in reality these machines were so ineffective that they probably did just that.

78
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This is the daisy number 2.

79
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Nice action, nice crank and bellows but I don't actually think it is getting anything off the carpet.

80
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And, er, this one is the baby daisy...
[clanking]

81
00:06:23,404 --> 00:06:26,432
though it's much bigger than the daisy number 2.

82
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[Clanking, squeaking and creaking]
It's slightly difficult coordinating all the actions at once.

83
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Doesn't seem to be doing too well either.

84
00:06:45,138 --> 00:06:53,381
Meanwhile in America a caretaker called Spangler had patented a portable vacuum cleaner powered by an electric motor.

85
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He sold the patent to a harness maker called Hoover who was worried that his trade was falling

86
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as more people changed from riding horses to driving cars.

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Hoover was very successful and started producing machines in other countries including Britain.

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# In the carpet, in the carpet, excavating through the pile

89
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worked a pit gang, called 'The Grit Gang', digging deeper all the while.

90
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Oh my carpet, oh my carpet, oh my carpet don't forget - with a Hoover, yes a Hoover, we will beat the blighters yet.

91
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# Oh my carpet, oh my carpet, oh my carpet don't forget - with a Hoover, yes a Hoover, we will beat the blighters yet. #

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Tim: The basic modern Hoover has really changed very little.

93
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We've cut part of this one away so you can see what's inside.

94
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This is the fan that does the sucking and it makes the brushes and beater bars go round as well.

95
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The dirt is dislodged by the rotating brushes, sucked straight through the fan and into the dust bag at the back

96
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The cylinder type of vacuum cleaner is slightly different.  It's actually more like Booth's original machine

97
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I'll take the bottom off this one...

98
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In this sort, the dust comes straight into the dust bag,

99
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and the air passes straight through the paper that acts as a filter,

100
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and goes through the fan and finally out the grille on the top of the machine.

101
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So the positions of the fan and the dustbag are reversed.

102
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And because it's only clean air which is passing through the fan the shape of the vanes can be much more intricate.

103
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So this sort usually has a much stronger sort of sucking power.

104
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And the bin type and the more modern flattened cylinder types are just the same as this,

105
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though the layout leaves slightly more room for bigger dustbags.

106
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The upright vacuum cleaner with a rigid dustbox is a sort of hybrid.

107
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We've cut one in half so you can see what's inside.

108
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It has rotating brushes just like a hoover,

109
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but inside the air and the dirt come straight up the back and into the dustbag,

110
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so its layout in some ways is more like the cylinder vacuum cleaner,

111
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because it's only clean air that comes out of the bottom of the dustbag and goes

112
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through the enclosed fan and then finally comes out the back of the machine.

113
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Well there are advantages and disadvantages of all these different types of vacuum cleaner

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and a recent Which survey found that in overall performance there's really very little to choose between them all.

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By the 1920s many companies were producing electric vacuum cleaners.

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Booth himself had started making them himself, under the trade name Goblin.

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One of his employees was a man called Bill Sutton.

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Bill: I joined Goblin in 1929, although I'd a relative with the company many years before,

119
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so I knew quite a bit about the vacuum cleaner business as a youngster.

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This model was produced in 1908 and appeared at the first Ideal Home Exhibition

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Bill to Tim: Would you like to do a bit of cleaning if I operate it?

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Tim: Oh I see it's a two-person machine?  Bill: Yes, oh yes.

123
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Bill: If I turn this handle, you do the cleaning.

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[chugging noise]

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Tim: It's getting something up.

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Bill: In fact they used to at the exhibition, have to go back to the factory and make another one if they sold one.

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Tim: Although better than most hand powered vacuum cleaners it was still rather inconvenient.

128
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so Booth started developing his own electric models.

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Bill: As you'll see it's got the old dolly switch and some very old fashioned flex.

130
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They wouldn't pass it with the approvals board today.
[chuckles]

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Tim: Where does the dust go?

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Bill: Well it actually goes in here.
Tim: Oh I see, yes.

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Bill: And you undo this to get at the dirt, to empty the machine.

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This machine was first produced in 1930, rather a unique machine

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in that it gives you the upright situation for easy cleaning.

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It sold for 5 pound, 19 and sixpence, at that time.

137
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But the interesting thing is that for dusting, all you need to do is undo the dustbag

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from this position here and put your arm through the dustbag and do your dusting.

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It did have some other tools for it, for dusting but of course that's another story.

140
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Bill: This particular model, a Goblin ace is 210 Volts, whereas today the standard voltage is 240.

141
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In the 30s, in Bristol there were two voltages, in London they went down as far as 100 Volts in certain places.

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Tim: Were there electricity shops where you could sell these things?

143
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Bill: Oh no. The electrical shops weren't in existence then, there was only a cycle shop who did the odd electrical product.

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[Footsteps] [Knocking on door]

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Bill: The industry had to employ vast numbers of direct-selling people,

146
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In fact Goblin had 2,500 at peak, of people knocking doors.

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Woman: Oh!

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Salesman: You've heard of the radio, you've now got electricity, but this is what you haven't got

149
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A vacuum cleaner! Look, it is...
Woman: Well I don't know...

150
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Salesman: No, look, I'll just take this wire, plug it into your sockets like that and we will have a demonstration.

151
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Salesman: If you are okay to stand up a minute madam,

152
00:12:32,296 --> 00:12:39,622
See! Now, did you know, in that chair is hidden dirt.  Every part of your house has got hidden dirt.

153
00:12:39,623 --> 00:12:43,524
Look, it's all in there now madam. Look. This is what you were sitting on.

154
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Woman: *gasps* Dust! Ohhh!

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Bill: The sales mostly had to be made of an evening, because the only person who was entitled to sign

156
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a hire purchase agreement was the husband

157
00:12:54,913 --> 00:13:00,664
and in most cases sales had to be made on a Friday or Saturday evening when the pay packet came in

158
00:13:00,665 --> 00:13:02,826
otherwise you didn't get the deposit.

159
00:13:03,427 --> 00:13:07,556
Tim: I'm now going to look at the various parts of the vacuum cleaner in greater detail.

160
00:13:07,557 --> 00:13:15,071
First the motor: electric motors are rather baffling devices but they all depend basically

161
00:13:15,072 --> 00:13:18,624
on the ability of electricity to magnetise things.

162
00:13:18,625 --> 00:13:23,371
If I wrap a bit of wire around a nail,

163
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Oh dear, got it tangled up...

164
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The more turns, the stronger the magnetism.

165
00:13:37,951 --> 00:13:45,108
I'm going to use 12V DC from a car battery, and of course you must never ever use mains for something like this!

166
00:13:45,509 --> 00:13:52,140
The nail becomes magnetic when I complete the circuit and when I break it again, most of the magnetism is lost.

167
00:13:57,841 --> 00:14:03,884
And if I wrap the wire around a little copper tube and hold it above the nail...

168
00:14:04,585 --> 00:14:09,122
then the magnetic attraction will pull the nail off the table.

169
00:14:09,123 --> 00:14:13,535
[Spark crackles] [clink...clink]

170
00:14:13,536 --> 00:14:15,742
(whispers) ...lets get it slightly more...

171
00:14:15,743 --> 00:14:19,721
[Clink clink]

172
00:14:19,722 --> 00:14:24,283
This is an industrial electromagnet, the coil of wire is in here,

173
00:14:24,284 --> 00:14:28,416
and this is the lump of metal it pulls in.

174
00:14:29,617 --> 00:14:36,398
This one's actually, um, out of a fruit machine, it's the device that pushes the coins out when you win.

175
00:14:36,399 --> 00:14:38,622
[coins clanking]

176
00:14:41,923 --> 00:14:45,381
Well I use these devices a lot on the machines that I make.

177
00:14:45,782 --> 00:14:50,960
I made this for a local solicitor, it was a portrait of the founder of the firm, his great uncle

178
00:14:50,961 --> 00:14:57,413
and he wanted to be able to control it, so it would react to his clients sometimes dubious confidences.

179
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[clunk]

180
00:15:00,499 --> 00:15:02,399
[Buzz]

181
00:15:03,000 --> 00:15:09,149
In the end he got cold feet, and placed the control box so that the clients themselves could use it.

182
00:15:09,150 --> 00:15:16,085
Well if you look at the back you can see that the device that makes the wig go up and down in the air

183
00:15:16,086 --> 00:15:18,696
is one of these electromagnets

184
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[BZZZZZT BZZZZT]

185
00:15:20,615 --> 00:15:25,491
And by themselves, these electromagnets can only produce this rather jerky, linear action.

186
00:15:25,492 --> 00:15:32,128
but it's not actually too difficult to use the electromagnetic attraction make something rotate.

187
00:15:39,029 --> 00:15:45,535
Rex: To show the principles of a simple electric motor, I've made a motor out of virtual rubbish:

188
00:15:45,536 --> 00:15:51,158
Nails, a hacksaw blade, an old needle, a cork and a dogfood can.

189
00:15:51,159 --> 00:15:59,063
The commutator, as the part in the vacuum cleaner motor I've made from a cork, with wires running up there.

190
00:15:59,064 --> 00:16:05,110
It acts as a sort of rotating switch, each wire is attached to a coil.

191
00:16:05,111 --> 00:16:10,064
When the wires are in contact with the brass strips, current passes through,

192
00:16:10,065 --> 00:16:15,537
so at one time, only one pair of coils are energised.

193
00:16:15,538 --> 00:16:22,368
These pair of coils here are magnetised by the electric current and they're attracted to this pair of coils,

194
00:16:22,369 --> 00:16:28,743
now when it pulls to there, these coils switch off and it brings on the next pair of coils,

195
00:16:28,744 --> 00:16:35,452
which are attracted to there, and of course they switch off bringing in the next pair causing a rotating motion.

196
00:16:35,453 --> 00:16:37,166
I'll switch on.

197
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[Grinding motor noise]

198
00:16:45,478 --> 00:16:50,117
Tim: The vacuum cleaner motor doesn't at first sight look like Rex's tin can motor,

199
00:16:50,118 --> 00:16:53,268
but if you look inside you can see it has a lot of the same elements.

200
00:16:53,969 --> 00:16:56,795
This is the commutator, the rotating contacts.

201
00:16:57,496 --> 00:17:01,352
These are the coils of wire rotating around the shaft,

202
00:17:01,553 --> 00:17:06,247
and these are the coils of wire round the outside making them both magnetic.

203
00:17:06,848 --> 00:17:09,650
Well in fact there are many different types of electric motor,

204
00:17:09,651 --> 00:17:13,258
but they all depend upon the basic ability of electricity to produce magnetism.

205
00:17:13,458 --> 00:17:14,858
[Baby babbles]

206
00:17:15,159 --> 00:17:20,689
It's really quite difficult to imagine how inconvenient the world must have been without any electric motors.

207
00:17:20,690 --> 00:17:23,158
Most of the machines in the home depend on them:

208
00:17:23,159 --> 00:17:29,961
Vacuum cleaners, power tools, washing machines, fridges, tape recorders and countless other gadgets.

209
00:17:30,262 --> 00:17:38,703
Steam engines, their predecessors, were hot and heavy and needed several hours stoking to get up pressure before they would work.

210
00:17:38,704 --> 00:17:43,005
Factories used to have a single steam engine connected to every machine in the place

211
00:17:43,006 --> 00:17:46,333
by a very elaborate set of belts and clutches.

212
00:17:46,334 --> 00:17:50,392
This was not very convenient or safe in a factory and totally impractical in the home.

213
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Baby: babble... babble... oooopsa...oooopsa...

214
00:17:53,799 --> 00:17:55,104
Man: OHHH!

215
00:17:55,205 --> 00:17:59,824
The bit that actually does the sucking is the enclosed fan next to the motor.

216
00:17:59,825 --> 00:18:03,676
I can show you where the air goes if I hold some smoke over it...

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[Vacuum cleaner noise]

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You can see that all the air is actually drawn straight through the middle of the motor to get to the fan,

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and the reason for this is that it helps to keep the motor cool.

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You can often feel the air coming out of the end of a vacuum cleaner is quite warm,

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and without this air passing through the motor it would very quickly overheat.

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The fan itself works with these rotating vanes, that whizz round and round and fling the air outwards.

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The air comes in the middle and the vanes go round flinging the air outwards, and then there's

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a second set of vanes that doesn't rotate, a static set, and these channel the air back to the middle again.

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And then there's another set, a second set of rotating vanes, that fling the air outwards,

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and finally there's a second set of static vanes that channel the air back to the middle again.

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[whirring noise]
And having these two stages doubles the suction power.

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Well one surprising thing about these fans is that they need less power to work when the inlet is blocked up.

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I can show you this, with this meter which shows how much current the motor is using.

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And, er, if I turn it on...

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[Vacuum cleaner noise]

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You can actually hear the pitch of the motor rising when I block the inlet up and that's because it's actually running faster.

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But of course it is also overheating because there is no air passing through it, so it's not really a very good idea.

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[Vacuum cleaner noise]

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The power of the fan is quite surprising, here we fixed the outlet of a vacuum cleaner to a plastic bag.

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The air pressure in the bag can quite comfortably lift my van off the ground.

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[Vacuum cleaner noise]

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The vacuum cleaner actually has the power to inflate things on a much larger scale.

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This is a pig built for the Pink Floyd by a local firm.

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Once it is inflated, a miniture car vacuum cleaner is enough to compensate

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for the air lost through any holes, and keep it full of air.

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And a full size vacuum cleaner can keep enormous things inflated.

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The only time I've ever used a vacuum cleaner, was for a machine which didn't need any of its impressive power.

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This is a collecting box I made for an charity society called 'Common Ground'.

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It's a sort of pun on its name showing a bit of ground being shared by different sorts of creature.

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The ground is actually a bit of rubber,

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I did my first experiments holding bits of rubber over a vacuum cleaner nozzle

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[Vacuum cleaner noise]

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Underneath, each of er, each footprint is connected to the suction pump at the bottom here, by one of these hoses,

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via a valve, each one by a separate valve, actually out of a washing machine.

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And this timer down the bottom here turns the valves on in sequence.
[motor noise stops] [ping]

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The last important part of the vacuum cleaner is the dustbag which acts as the filter.

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The paper of cloth contains minute holes which trap most of the dirt, but let the air pass straight through.

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Of course any bits of dirt that are smaller than the size of these holes

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which are about 1/200th of a mm in diameter, will pass straight through the bag.

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I can show you this with this smoke cartridge that contains minute particles of red dye.

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If I put it next to the nozzle, you'll see the dye come straight through the machine and out through the grille here.

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[Click]

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Oh I forgot to turn it on.

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[Vacuum cleaner noise]

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Normally about 15% of household dust is below this critical size and passses straight through the machine.

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[Vacuum cleaner noise continues]

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Rex used to repair domestic appliances, and found often people didn't realise this.

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Rex: Sometimes I would be called out to a machine that wasn't working, and the customer

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had actually fitted a plastic bag inside the cloth bag so they could dispose of the dirt easily.

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Well this of course completely blocked the airflow and there was no suction at all, and obviously it wouldn't work.

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Even the disposable paper bags need changing quite frequently,

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some customers used to use one paper bag and empty it continuously.

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And they do lose their efficiency, and the little pores in the paper get blocked with dust and they just don't work.

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Occasionally, one or two clients had actually had a machine for ten years or so,

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and they'd still got the original packet of paper bags, and had only ever used one.

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Tim: The vacuum cleaner is really quite a simple machine, a motor a fan, and a dustbag.

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But it does have a particularly hard life being pushed and tugged about all the time.

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Although they used to be sold with lifetime guarantees, today they rarely last more than a few years.

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The modern vacuum cleaner may not be perfect, but it is extraordinarily good value for money.

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In 1950 a vacuum cleaner cost about the same amount as the average weekly wage.

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Today, it costs a lot less than half that.

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An enormous amount of energy and cunning has gone into reducing the manufacturing costs,

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and perhaps for their price today we can't really expect them to last for very long.

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Although vacuum cleaners are now rather flimsy and unsatisfying machines, and their

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short lifespan is ecologically very unsound, they do retain more character than most

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[rocket ignites] ...other household machines, and I can't help rather liking them.

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[rocket noises continue]

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[Jazzy music: 'Take 5' - Dave Brubeck]