The shadows are softened so as almost to leave no trace, and
we have what artists call an atmospheric effect. If we go into another
climate, such as Egypt or among the high Alps, we usually lose this
effect. Distant mountains stand out crisp with black shadows, and the
want of atmosphere is much felt. [Photographs showing these differences
were shown.] Let us ask to what this is due. In such climates as England
there is always a certain amount of moisture present in the atmosphere,
and this moisture may be present as very minute particles of water--so
minute indeed that they will sink down in an atmosphere of normal
density--or as vapor. When present as vapor the air is much more
transparent, and it is a common expression to use, that when distant
hills look "so close" rain may be expected shortly to follow, since the
water is present in a state to precipitate in larger particles. But when
present as small particles of water the hills look very distant, owing to
what we may call the haze between us and them. In recent weeks every one
has been able to see very multiplied effects of such haze. The ends of
long streets, for instance, have been scarcely visible, though the sun
may have been shining, and at night the long vistas of gas lamps have
shown light having an increasing redness as they became more distant.
Pages:
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130