REPORT OF ASSISTANT SECRETARY. 35 



with vaseline. The junction tlius loriiu'd is so perfect that it is neces- 

 sary to have a vent-hole in the toj), thouiih much smaller than is custom- 

 ary, it l)eing only one-sixteenth of an inch in diameter. Jars made in 

 this way, of the size already alluded to as costing- more than §100 a 

 dozen, can certainly be had for a little more than half the price and, if 

 they prove permanent, will be iu every respect better. 



Photographs have been made from jars filled with alcohol and speci- 

 mens, and the peculiarities of the two systems are shown without dis- 

 tortion or exaggeration iu the accompanying plates (Pis. 13 and 14). 



A small built-up jar, made in Germany, has been in use in the Army 

 Medical Museum and elsewhere as an accessory to the microscope. 

 These jars will hold all liquids and acids used in microscopic work, 

 and careful examination shows that the cement used is subjected to a 

 vitrifying heat. The use of hot water in the jars breaks them in the 

 corners, which uuike natural lines of cleavage. Just how large a jar 

 can be made in this way we have no information, but some of the 

 ex])eriments tried by us demonstrate that thej' are not as reliable as 

 those nmde with cemented corners. 



A convenient way of mounting specimens for the rectangular jars is 

 shown in fig. 8. The fish or other object to be mounted is fastened to 

 a pane of common Avindow glass by means of threads passed through 

 the object, ordinarily by the use of a surgeon's needle. These are 

 drawn through holes bored in the glass at the proper places, and 

 fastened by breaking off a soft wooden peg in the hole, biting and fas- 

 tening the thread in place. The holes are readily bored by aid of a 

 solution of turj)entine and camphor used as a lubricant, and a small file 

 as a drill, held in a small drilling macbine. Any jeweler's supi)ly store 

 can furnish the requisite material. 



THE PREPARATION OF LABELS. 



The preparation of labels is one of the most difticult tasks of the 

 museum man. The selection of the descriptive matter to be printed 

 requires the best of judgment and the widest and most accurate 

 information; while to determine the form and size of the ditt'erent 

 labels in a series, and to secure the best typographic effect, is equally 

 difficult, and requires abilities of quite a different order. 



A label may contain a vast amount of exact and valuable informa- 

 tion, and yet, by reason of faulty literary and typographic arrange- 

 ment, have as little significance and value as a piece of blank ])aper. 



Before a specialist is prepared to label a collection he must be a 

 complete master of the subject which the collection is intended to illus- 

 trate. After he has written the series of labels, if the collection is 

 coniplete, he will have the material under control which would enable 

 him to write a very complete book of reference upon the subject. 



No task is more exacting than label writing. Not only is it impossi- 

 ble to conceal any lack of precise knowledge, but the information must 



