October 22, 1909] 



SCIENCE 



551 



from time to time and even turned over, 

 when one surface is too far gone for plan- 

 ing. Such tops have been known to last 

 with constant usage in an organic and 

 analytical laboratory' for nearly thirty 

 years. These plank tops should be made of 

 lumber as wide as possible and be carefully 

 jointed and well glued together. When 

 properly done it is rare that the glued 

 joint starts. From some laboratories which 

 the writer has seen it would not seem ad- 

 visable to build the tops of narrow seven 

 eighths inch floor boards even when fast- 

 ened to a second seven eighths inch top ; the 

 joints open and the boards warp and curl 

 making a very undesirable, uneven surface. 



Desk Eardivare.— For locking the desks, 

 iron hasps and screw eyes and heavy pad- 

 locks have given excellent satisfaction even 

 with freshmen, for twenty- five years' con- 

 stant use. These locks^ are bronze through- 

 out, with brass or bronze springs and six 

 secure levers, master-keyed, with changes 

 permitting at least four hvindred in a 

 series: they are circular, except for the 

 shackle, and about two and one fourth 

 inches in diameter and cost about a dollar 

 each. They should be oiled annually with 

 a light non-gumming petroleum spindle 

 oil. Padlocks have the advantage over mor- 

 tise locks, keyed or keyless, in that if they 

 fail to open the screw eye can be cut with 

 a blacksmith's bolt cutter, the padlock re- 

 moved and the cut screw eye replaced by 

 another. The damage to the desk is noth- 

 ing compared with that incident to forcing 

 a drawer or hammering the lock loose or 

 off by a punch on the round key-hole 

 standard. They have the additional ad- 

 vantage that they, being laid on their side, 

 in the drawer when not in use, are not ex- 

 posed to the corrosive action of chemicals 

 spilt upon them. These run down the mor- 

 tise lock around the bolt and levers and 



■Made by the Miller Lock Co., Philadelphia, Pa. 



stick them fast. Their sole disadvantage, 

 as against combination locks, lies in the loss 

 of the key. The losing of keys can be 

 largely prevented by requiring the use of 

 key chains attached to the bunch of keys 

 and also by informing the student that they 

 are charged one dollar each if lost. They 

 have the advantage that they are much 

 more easily opened, while if the combina- 

 tion be forgotten the instructor has to 

 search it up in the records. Unless the 

 combination on each lock be changed an- 

 nually, an elder student, a sophomoi-e, for 

 example, would have access to the desk 

 which he used as a freshman, which is now 

 occupied by another student, a serious dis- 

 advantage. The changing of several hun- 

 dred combinations annually is no trifling 

 task. Hard-wood knobs are to be preferred 

 to metal knobs or handles. The Fogg ad- 

 justable ball catch with the ball on the 

 standing part of the desk has given excel- 

 lent service. Iron hinges are apparently 

 as good as brass and are cheaper. 



Piping and Drainage. — All pipes and 

 drains should be arranged so that every 

 foot can be easily rendered accessible for 

 inspection and repairs. This can be 

 brought about bj' the "top system" of 

 pipes and drains on the desks and these 

 connected with the main sj'stem under 

 platforms running along one end of the 

 desks. Or the piping can be arranged upon 

 the back of one line of desks and the other 

 line, which is movable, backed up to it. 

 Iron piping should be used as far as pos- 

 sible, the outside being painted with a 

 pitch or asphalt paint. Lead lined pipe 

 instead of lead would seem to be satisfac- 

 tory for suction. For peaty service waters, 

 black pipe fills up rapidly with zooglea, 

 crenothrix and iron rust. This can be 

 avoided to a large extent by the use of gal- 

 vanized iron or lead-lined pipe. For 

 drainage the lead-lined or even plain 



