BAIRD &TATLOCK (LONDON) LTD. 



No. 26. Water Hammer. A glass tube containing water in a vacuum, illustrating the 



cause of some of the noises in water pipes . . . . . . . . ..040 



No. 27. Radiation. Small glass model with vane delicately poised in vacuum, which 



will readily revolve when exposed to sunshine or artificial light . . ..0100 



No. 28. Water Tests. For class demonstration or cursory examination, and most 

 useful for Teachers and Sanitary Inspectors, giving reliable information of serious 

 contamination. Complete, with instructions for use, which can be carried out without 

 chemical experience . . . . . . . . . . . . ..150 



No. 29. Radiation, Conduction, and Convection. An exceedingly effective and useful 

 working model. Illustrating the three laws of heating by hot water, hot air, conduc- 

 tion of metals and direct radiation. Can be fixed against a wall like a picture frame. 

 Size 2 ft. by 2 ft. 6 in. . . . . . . . . . . . . . . 4 4 



No. 30. Septic Tank. A complete model of the sewage liquefying tank, with movable 



top to show interior. Made to scale about 15 in. long .. *.. .. .. 1 10 



No. 31. Barker's Mill. Working model to illustrate one of the most popular methods 



of sewage distribution, known as a " Sprinkler " . . . . . . 1 15 



No. 32. Water Ram. A small working model in glass . . . . . . . . 086 



No. 33. Lactobutyrometer. Marchand's process. A thoroughly reliable Milk Test 



for determining the percentage of Butter Fat in milk. No chemical knowledge 



required ; accurate results in a few minutes. Complete, with instructions and 

 chemicals for about thirty tests . . . . . . . . . . 17 6 



No. 34. Barometer Scale and Vernier. Suitable for class work . . ..050 



No. 35. Water Filter. Section of large sand filter (J scale) typical . . ..330 



No. 36. Water Filter. (Pasteur Chamberland), in nickel case . . ..150 



No. 37. Sherringham Valve. Fitted on wooden stand . . . . ..076 



No. 38. Tobin's Tube. Fitted on wooden stand . . 076 



No. 39. Mica Flap Valve. Fitted on wooden stand . . . . . . 076 



No. 40. M'Kinnel's Cowl . . . . . . . . . . ..076 



No. 41. Water Pipes. Set, including Tin-lined Iron, Tin-lined Lead, Glass-lined Iron. 



Iron, with Angus Smith's Solution . . . . . . . . . . ..076 



No. 42. Sanitation Models. Suitable for Hygiene Classes, including Hopper W.C., 

 Wash-down W.C., Bath, Sink, Gulley, Interceptor, Junction, Pipes (2 sizes), Taper 

 Pipe, Bend, P. & S. Traps, Straight Channel, Channel Bend, Model Bricks (3), Damp- ' 

 proof Course, Ellison's Air Brick . . . . . . . . . . ..220 



No. 43. Board of Education Set. Comprising Ellison's Air Brick, Sherringham Valve, 

 Tobin's Tube, Mica Flap Valve, Sediment Trap, Intercepting Trap, Junction Pipe, 

 Drain Pipes, Channel Bend, Gully Trap, Sink, Wash-down Closet, Bath, Long Hopper 

 Pan, Damp-proof Course Water Pipes, Tin-lined Lead, Tin-lined Iron, Glass-lined 

 Iron, and Smith's Solution coated Iron, DipstoneTrap (model), and Model Barometer 

 Scale with Vernier. Complete Set, including Box . . . . . . . . 440 



5996 s " Diagrammettes." Single sheets from " Diagrammette " Book giving a separate 

 diagram with descriptive matter, suitable for distribution to students at classes or to 

 .large audiences. This is a most satisfactory method of teaching . . per hundred 040 



1 8 



.CHEMICAL AND SCIENTIFIC APPARATUS AND PURE CHEMICALS. 



1095 



