STBENGTH OP GLASS,
630
Comparison of strength for different methods of manufacture.
WIRED PLATE. 24-INCH SPAN.
Thickness.	Modulus of rupture per square inch.		The stronger glass.
	Sandwich rolled.	Solid rolled.	
	Pounds. 5,050 4,530 4,670	Pounds. 4,840 3,710 4,130	Sandwich. Do. Both sandwich rolled.
			
			
			
WIRED PLATE. 16-INCH SPAN.
£ inch		4,200	3,670	Sandwich.
j inch		4,220	3,620	Do.
i inch		3,840	4,010	Both sandwich rolled.
Comparison of strength for different methods of annealing.
POLISHED PLATE. 24-INCH SPAN.
Thickness.	Modulus of rupture per square inch.		The stronger glass.
	Oven annealed.	Lehr annealed.	
	Pounds. 8,120 6,780 4,030 5,040 6,280 4,910	Pounds. 6,090 6,710 5,560 5,630 6,440 4,290	Oven. No practical difference. Lehr. j-All oven annealed.
			
			
			
			
			
			
Comparison of strength of the different kinds of plate.
24-INCH SPAN.
Thickness.	Modulus of rupture per square inch.								The strongest glass.
	Rough.		Ribbed.		Wired.		Polished.		
i inch ... i inch ... 5 inch ...	Pounds. 7,410 4,770 5,160	Pounds. 6,310 5,870 4,240	Pounds. 6,850 5,150	Pounds. 6,890 5,250	Pounds. 5,050 4,530 4,670	Pounds. 4,840 3,700 4,130	Pounds. 5,560 5,630	Pounds. 4,030 5,040	Ribbed. Rough. Polished.