talks in political campaigns, 340 Legend for charts, 360 ,

Lenses, camera, 330

cylindrical, 330 "Less than" basis for frequency curves, 179 Lettering on charts, 26, 82 Letters of appeal for money, 250

gummed, 46 , •

Lighter operation, chart for, 56 Line cuts from pin maps, 234

made from green ink, 330, 331 Line thickness in reduced drawings, 242 Lines connecting different bars, 31 Loans to industrial employees, 156 Locomotive feed-water curves, 159 Logarithmic co-ordinates, 132

paper, 334, 362

ruling, 334

scale for curves, 132 Lorenz curve, 197 Lorenz, M. O., 197 Lubrication cost at a factory, 256

Manufactured products of cities, 23 Map and pin systems, 226 Map copyrights, 237

models, 225

pins, 225

pins used for cost analysis, 192

Map pins with numbers, 243, 247

presentations, 208

tacks, 225 Maps, coloring, 209

for corporation records, 293

for election returns, 341

for wall use, 225, 229

mounting of, 231

shading, 209 Marx, Guido H., 334 Mass curves, 149 Massachusetts Institute of Technology,

11, 198 Mazda lamps, 337 McAbee, WiUiam D., 245 McGraw-Hill Book Co., 335 Mechanical shading, 331, 332 Merchant tonnage of United States, 112,

Methods, general, 321

Metropolitan Sewage Commission, 20, 85 Milk-analysis curves, 114 Milk-production curves, 278, 279 Misleading figures, 326 Mode, 165, 170 Models, card-board, 336

solid, 336 "More than", basis for frequency curves,

Morgan, J. P. & Co., 15 Motion picture cameras for time study, 50 Motor, 346, 347 Motor trucks, cost for gasoline, 198

cost of operating, 11 Mount Holyoke College, 167, 176 Mounting maps, 231 Moving-average curves, 97, 283 Municipal parades, 343