74 THE HERB-GARDEN 



it has much the same smell and properties. It 

 is remarkable that such water-loving plants as 

 Mints should be aromatic. As a rule, aromatic 

 plants belong to hot, dry places. The essential 

 oil in their leaves serves. Professor TyndaU tells us, 

 to protect them from the intense heat of the sun ; 

 the passage of the heat rays is hindered. The late 

 Professor made a series of experiments, too, as to 

 the absorption of heat by odorous vapours. Air 

 scented with patchouU had thirty times the cooling 

 effect of fresh air, and cassia had actually one 

 hundred and nine times the effect. Do we not all 

 know how a spray of perfume diffused about a room 

 will cool it ? Rowing men, when resting in some 

 leafy Peppermint- scented backwater on a hot day, 

 must have noticed what a coohng, refreshing influ- 

 ence is somehow spread around. Let me ask them 

 next time this happens to give a grateful thought 

 to the wild Mints. I believe they deserve it. 



Pennyroyal grows quite differently from the 

 other Mints. It creeps about close to the ground, 

 and used to be known as ' Lurk-in-the-Ditch,' or 

 ' Run - by - the - Ground.' ' Pudding - Grass ' was 

 another name for it, because it was used in hogs' 

 puddings. Gerarde, whose garden at Holborn 

 flourished in Queen Elizabeth s time, said : ' It 

 groweth naturally wilde in the Common near 



