These observations apply to the Public General Acts of the legislature. On the other hand, in settling private Acts, such as those relating to railway and canal enterprise, the legislature always inserted certain clauses founded on reasons of public policy applicable to the business in question. To avoid the necessity of constantly re-enacting the same principles in private Acts, their common clauses were embodied in separate statutes, and their provisions are ordered to be incorporated in any private Act of the description mentioned therein. Such are the Lands Clauses Acts, the Companies Clauses Acts and the Railways Clauses Acts.