PREFACE x1 
chasers is concerned. The use of so-called ‘ pre- 
servatives,’ such as salicylic acid, etc., are not only 
hurtful to digestion in themselves, but they enable bad 
food to be eaten, and so doa double injury. Glucose 
and colouring matter in cheap jams, water in milk, 
foreign fats in butter, sugar and arsenic in ale or beer, 
are only a few of the pitfalls laid for us in the market- 
place every day of our lives. This is merely one way 
of emphasising the fact that all our senses, however 
cultivated and acute they may be, are open to deception. 
Even ‘‘the pure air of heaven” becomes vitiated in 
towns, and there are so-called improved kinds of sanita- 
tion that lead to infection. The little London school 
boy when asked what a fog was, replied that he didn’t 
quite know, but he thought it was ‘‘a mist that couldn’t 
fly away!” Our London fogs now reach into the 
suburbs and beyond for miles, and do incalculable injury 
to vegetation outside, as well as to flowers or other 
market-garden products under glass roofs. We must 
all do our best to encourage Sir O. Lodge in his attempts 
to banish fogs or mists by electrical discharges. Anyone 
who can do away with the enormous waste and countless 
other evils of coal smoke and fog, will revolutionise 
existence in large towns, and save the enormous losses 
now suffered by market-gardeners and florists, especially 
near London. From Evelyn’s time in 1661 until to-day, 
the fog problem has defied chemists, physicists, and all 
other scientific men, and even modern London and County 
Councillors and others seem as far off its solution as ever. 
POWs 
