Drainage for Melbourne. 53 



themselves, the rapid flow resulting from the smoothness and 

 small diameter of the pipes is sufficient. 



4. Facilities for maHcious stoppage. 



This objection equally applies to the ordinary water closet, 

 which any spiteful servant can easily render useless ; but it has 

 not yet been argued that therefore water closets are inferior 

 to the common privies and cesspools. And besides, it would 

 not be easy to show wherein the presumed facility in this 

 case consists. 



There are other objections, principally based on the diffi- 

 culty of getting at the point of obstruction whenever it occurs 

 in these drains. At the first introduction of the system 

 much difficulty did exist, as any one may easily conceive, who 

 has seen our ordinary gas mains laid down, in which the 

 removal of any pipe on the line is a matter of much trouble, 

 and the efficient substitution of another not easily effected. 

 But recent improvements in the junction of drain pipes have 

 obviated the objection alluded to ; a species of lid, with a 

 flange, forming the top joint, and being easily removable with- 

 out disturbing the main pipes. Hence, with manholes and 

 pressure guages for examination at a few points, the locality 

 of any obstruction is easily ascertained, and the obstacle as 

 easily removed as in a brick sewer of large size. 



The advantages of the tubular system may be thus summed 

 up. It is very much less costly than brick sewers, for 

 instance : — The town of Rugby was drained by pipes varying 

 in diameter from six inches to twenty inches at a cost of 

 £3,600, while brick sewers would have cost ,€15,000. Occu- 

 pying less area in height, it admits of better fall, and by the 

 acceleration and concentration of its flow secures both the 

 rapid transmission of refuse and the diminution of stench. 

 The impermeability of the pipes prevents the percolation of 

 noxious matter into the adjacent soil. The tubular system 

 is moreover impregnable to rats. In illustration of this point 

 of advantage, I may refer to the large revenue said to be 

 derived by the periodical sale of rat skins (after flushing) to 

 the glove makers of Paris. 



But whilst admitting the advantages of the tubular system, 

 it should be borne in mind that, to secure all the desired 

 benefits, it must be honestly and efficiently carried out. 

 Most of the defects that have been urged against it as a 

 system, have in reality arisen from bad workmanship. The 

 others have been obviated by improvements of the system 

 itself. Allow me to touch slightly upon this part of the sub- 



