"(6th) Any other combination that cannot be entered into under the basis of this tariff, will be arranged by specially agreed upon prices, such agreement being as much as possible subject to the basis mentioned." _Sanitary Regulations._--The State Government, on March 1st, 1909, published regulations for the proper installation of the water and drainage services within the houses. At the Government's request, a draft of the proposed regulations was submitted by the writer, who prepared it, after a study of American and British sanitary by-laws, to suit the special conditions of Monterrey. These regulations were afterward modified by him in collaboration with the Government Technical Inspector and Financial Interventor, and, in their final form, though not as stringent as those adopted in many northern cities, are probably more complete than those in any other Mexican city. Under these regulations only registered plumbers can undertake plumbing installations, and they have to execute a bond to the satisfaction of the _Alcalde Primero_ (City Mayor) for the sum of 2,000 pesos as a guaranty of responsibility. For defective workmanship or any infraction of the plumbing regulations, they are liable to heavy fines, and can be called on to make good all defects in workmanship, without extra charge to the owner of the property. The provisions of the regulations are carried out under the supervision of the Government Technical Inspector, the Company's obligations extending only to the sidewalk and to the meters placed within the houses. ENGINEERS, ETC. G. S. Binckley, M. Am. Soc. C. E., was Chief Engineer of the Company from February to December, 1906. The writer was Chief Engineer from May 1st, 1907, until April, 1910, and is responsible for the design and construction of the works carried out during that period. Mr. J. D. Schuyler advised the Company throughout all preliminary studies and investigations, and acted as Consulting Engineer until February, 1908. The Technical Inspector, on behalf of the Government, throughout the whole progress of the works, has been Rudolf Meyer, M. Am. Soc. C. E., and the writer wishes to record the valuable assistance the Company has received from him. In conclusion the writer may be permitted to pay a tribute to the devoted public spirit shown by his Excellency, General Bernardo Reyes, the Governor of the State of Nuevo Leon from 1885 to February, 1910, and who, untiring in his devotion to the interests of the city, was primarily responsible for the inception of the works and their successful completion. DISCUSSION.