Trans: IN. VA. Scé. 142 Mar. 13, 
introduced from time to time, until the plug was driven out by the force 
of the explosion of the mixture of vapors and air within. 
At first sight this appears to be the acme of oil-toilers; but, alas, it 
has several important faults. It is not a matter of indifference how the 
plug is placed in the tube. If it is too tight, it will not be ejected by 
the explosion, and the flame wili force itself out at the side valve. Itis 
also important that the instant of right admixture of vapors and air 
should be the instant that the flame is introduced. For if the air con- 
tains more vapors than will form an explosive mixture, simple combus- 
tion at the valve, and not explosion, is the result. By introducing the 
electric spark as a means of ignition, the difficulty of admixture may be 
overcome; but the force necessary to eject the plug must always be a 
difficulty. 
In this paper I have not been able to discuss all the various appa- 
ratus used for testing kerosene oil; but I have taken some of those most 
used, and that are types of others. 
Yet one other apparatus remains to be noticed, and this is the “ elec- 
tric closed tester,” devised by Mr. PEASE, of Buffalo. In this appa- 
ratus we have the usual oil-cup and water-bath. But the oil-cup has a 
cover, and an overflow tube to insure the level of the oil remaining the 
same during the process of hea!ing ; since the heating causes expansion 
of the oil and thus raises the level. Into the cover of this tester are fitted 
two wires, between which a spark from an induction-coil may be passed. 
The usual outfit of thermometers completes the app2ratus. 
This apparatus is very nicely made, and the overflow-tube is an im- 
portant device, especially with the heavier oils. But, in working with 
this tester, I was surprised to obtain results very little better than with 
an open tester. This is due to the fact that the spark-wires are in the 
centre of an opening in the cover, and that this opening is so large that 
the vapors escape around the sides without being ignited. To prove 
this, I covered the opening with a small piece of glass, and obtained a 
flash at a much lower temperature, because the vapors could not escape. 
For the sake of comparison, I have tabulated the results obtained 
with the various apparatus, and the quantities of oil used in each. 
| 
| Oil Used. Flash. 
‘AteWesbelopbletcys (esl) ls Goodooongoncocdenncoteconeeecene 2 ounces 97° Fah. 
DAVDOlt Si (OPEN) jets ctetowr eile aia eso ler cvoutoevetie mel ntole sor eae [ese 8s ooyaness 
Maoiiabue si(Closed)\t scence seec ree occ ete fo cent. | 3 se oe) 
Agelis \(closed)) xa5.tas have asa seisiand acieiopometeercrats ids eae 2% « 7. eae 
BESrNsleim1ss (CLOSED) io. crsiejnia syareis eloteisefasem eee ef Seeks |: mage es TOON 
SWisconsin: (Closed) xe. ..c a ecsta see eile eee eye mie hans mx lon | Gt 
Mann) Ss: (CLOSER) aeisiae ls) shes srontnete io ein rstereteeaty ae ast | ro i 75 
