1. Introduction  
2. Observations and Data Reduction  
2.1. Source Selection  
2.2. Herschel Observations  
3. Results  
3.1. Distance Determination  
3.2. Profile Decomposition  
3.3. Correlations Between Dust- and Gas-Derived Physical Parameters  
3.4. Column Densities and Molecular Abundances  
4. Discussion  
4.1. Average Physical Conditions in the ℓ=30° and ℓ=59° Regions  
4.2. Gas Kinematics  
4.3. Association with Maser Emission  
4.4. Evolutionary Trends  
5. Summary and Conclusions