Excerpt from Thirty-Fifth Annual Report of the Provincial Board of Health of Ontario, Canada, for the Year 1916 Clay, Location of Sewer Pipe Clay in Ontario Cla

Excerpt from Thirty-First Annual Report of the Provincial Board of Health of Ontario, Canada, for the Year 1912 TO the honourable W. J. Hanna, k.c., Provincial

Excerpt from Thirty-Eighth Annual Report of the Provincial Board of Health of Ontario, Canada, for the Year 1919 I herewith beg to present for your consideratio

Excerpt from Thirty-Fourth Annual Report of the Provincial Board of Health of Ontario, Canada: For the Year 1915 May IT please your honour - I herewith beg to p

Excerpt from Thirty-Sixth Annual Report of the Provincial Board of Health of Ontario, Canada: For the Year 1917 Elsewhere is given in greater detail information