|                                                  |
   |      3,3V                      A4                |
   |   9~    Gnd                 A5                   |
   +-//+//+//+--//---------------+//+--//-------------+
       |  |  |                   |  |  
       |  |  |                   |  |  
       |  |  |                   |  |  
       |  +----------------+     |  |  
       |  |  +----------------+  |  |  
       |  |  |             |  |  |  |  
       |  |  |             |  |  |  |  
   +---+--+--+---+     +---+--+--+--+--+---+
   |   Dat   Gnd |     |   VCC   SCL   3,3 |
   |      VCC    |     |      Gnd   SDA    |
   |             |     |                   |
   |    DHT11    |     |      BMP180       |
   +-------------+     +-------------------+

The pull-up-resistors, typically 4k7, had not been connected between each SCL
and SDA to VCC. You may use them, but the circuit works anyway.