  We demonstrate experimentally the generation of one-dimensional cold gases of
$^{87}$Rb atoms by diffuse laser cooling (DLC). A horizontal slender vacuum
glass tube with length of 105~cm and diameter of 2~cm is used in our
experiment. The diffuse laser light inside the tube, which is generated by
multi-reflection of injected lasers, cools the background vapor atoms. With
250~mW of cooling light and 50~mW of repumping light, an evenly distributed
meter-long profile of atom cloud is obtained. We observe a factor 4 improvement
on the atomic OD for a typical cooling duration of 170~ms and a sub-Doppler
atomic temperature of 25~$\mu$k. The maximum number of detected cold atoms
remain constant for a free-fall duration of 30~ms. Such samples are ideal for
many quantum optical experiments involving electromagnetically induced
transparency, electronically highly excited (Rydberg) atoms and quantum
precision measurements.
