250 Peckham — Nitrogen Content of California Bitumen. 



that kind of thing with the solar parallax. I do not think 

 there is an}* exaggeration in saying that the trustworthy obser- 

 vations now on record for the determination of the numerous 

 quantities which are functions of the parallax could not be 

 duplicated by the most industrious astronomer working con- 

 tinuously for a thousand years. How then can we suppose 

 that the result properly deducible from them can be materially 

 affected by anything that any of us can do in a life time, 

 unless we are fortunate enough to invent methods of measure- 

 ment vastly superior to any hitherto imagined ? Probably the 

 existing observations for the determination of most of these 

 quantities are as exact as any that can ever be made with our 

 present instruments, and if they were freed from constant 

 errors they would certainly give results very near the truth. 

 To that end we have only to form a system of simultaneous 

 equations between all the observed quantities, and then deduce 

 the most prpbable values of these quantities by the method of 

 least squares. Perhaps some of you may think that the value 

 so obtained for the solar parallax would depend largely upon 

 the relative- weights assigned to the various quantities, but 

 such is not the case. With almost any possible system of 

 weights the solar parallax will come out very nearly 8-809" 

 iO'0057", whence we have for the mean distance between the 

 earth and sun 92,797,000 miles, with a probable error of only 

 59,700 miles ; and for the diameter of the solar system, 

 measured to its outermost member, the planet Neptune, 

 5,578,400,000 miles. 



Aet. XXXIV*— On the Nitrogen Content of California 

 Bitumen; by S. F. Peckham. 



[Read at the Con°-r§$s of Chemists held at San Francisco. Cal., in association 

 with the Midwinter Fair, June 9th, 1894.] 



In 1865, when artificial excavations in the Canons of the 

 Sulphur Mountain in Ventura County, California, brought to 

 the surface bitumens that were free from the action of oxidiz- 

 ing agents, it was soon observed that when those bitumens were 

 exposed in small pools for a short time they became infested 

 with maggots. This phenomenon was observed by a number 

 of persons. In one instance that came under my own observa- 

 tion, the amount of petroleum that filled a small cavity in the 

 rocks might have been two quarts. It was so filled with mag- 

 gots that they crawled over each other precisely as they would 

 in a pool of blood. It was evident that this petroleum con- 



