EXHIBITION OR PERMANENT STORAGE. 



127 



expensive than jars of the same capacity, but are less subject to injury, especially during 

 transportation. 



A convenient size has the following dimensions : Height, 30 cm. ; diameter, 40 cm. ; 

 diameter of the orifice, 26 cm. ; capacity, 30-35 liters. The rings of the screw-top are made 

 of brass, and should not weigh over 1300 grams. The bottom should be protected from 

 abrasion by bosses. (At the Museum of Comp. Zoology in Cambridge each can is enclosed 

 in a wooden case which facilitates handling and may be used in transportation.) The edge 

 of the cover-ring is notched for the admission of the iron bar with which it is screwed or 

 unscrewed. Such a can costs $10-$12 ; this is more than the cost of a glass jar of 

 equal capacity, but the latter is liable to break, especially during transportation, while the 

 can is practically indestructible. 



311. Glass Jars. With the exceptions indicated in the fore- 

 going sections, glass is to be preferred for all alcoholic specimens. 

 Glass jars may be considered in five groups : fruit jars ; specimen 

 jars with covers ; specimen jars with neck and ground glass stop- 

 pers ; welted jars ; compressed jars. 



312. Fruit Jars. There are many styles of these, but most of them are made of 

 more or less opaque glass. The orifice is seldom more than' 5.5 cm. in diameter. They 

 are thus unsuited for exhibition or for holding wide specimens ; but their cheapness and 

 strength adapt them well for the storage and transportation of such specimens as they 

 will contain. 



FIG. 32. WIDE MOUTHED SPECIMEN JARS WITH COVER ; 8 312. 



313. Wide Mouthed Jars with Covers (Fig. 32). These are made on the general 

 pattern of the "Millville" fruit jar, but are of clear glass, and have mouths nearly as 

 wide as the jars ; the cover has a ring from which specimens may be suspended. Messrs. 

 Whitall, Tatum & Co., in addition to what is said in their catalogue (A, 2600), will send a 

 price list of 13 sizes, ranging from 4x3 in. to 23 x 9. The following special lengths of 

 standard widths have been made by the same firm at the following prices for each jar : 

 18 x 3 in., $1.15 ; 23 x 4, $2.05 ; 32 x 4, $3.30 ; these tall jars are provided with a " foot." 



These jars are of course less handsome than the glass stoppered kind, but their strength 

 and cheapness well adapt them for museum and laboratory use. 



