~74. The Special Advantages of Mineral Oils~ as lubricants in horology are:

1. Mineral oils can be made entirely pure, and possess uniform and known properties when derived from the same or a similar source; while the quality of animal and vegetable oils varies from year to year, depending, in animal oils, on the season of the year when the crude oil is obtained, on the age and condition of the animal, and on the kind, quality and quant.i.ty of food which it had (5) recently consumed; and in vegetable oils on the season, soil, climate and method of treatment.

2. According to Thurston "All vegetable and animal oils are compounds of glycerine with fatty acids. When they become old, decomposition takes place and the acid is set free, by which action the oils become rancid.

This rancid oil or acid will attack and injure machinery. Again, all animal oils contain more or less gummy matter, which acc.u.mulates when exposed to the action of the atmosphere, and will, consequently, r.e.t.a.r.d the motion of the machinery."

3. Spon, in his Encyclopedia of the Arts, gives his views to the effect that "The best oil is that which has the greatest adhesion to metallic surfaces and the least cohesion in its own particles. In this respect fine mineral oils stand first, sperm oil second, neatsfoot oil third.

Consequently the best mineral oils are the best for light bearings. The best oil to give body to fine mineral oils is sperm oil."

4. "Mineral oils do not absorb oxygen," and consequently do not "gum" or become viscous.--Thurston.

5. Mineral oils never become rancid in any climate, as they possess no fatty acids.

6. Mineral oils produce very little fluid friction.

7. Mineral oils withstand a high temperature without decomposition or vaporization, and a low temperature without solidification.

8. Properly prepared mineral oils are free from grit and all foreign substances.

9. In addition to the above, a minor property of mineral oil is that they are very cheap comparatively, while they do not possess any odor if properly refined.

10. The variation of viscosity in varying temperatures is less in mineral oils than in animal or vegetable oils.

~75. Methods of Testing Oils~ are necessary in order to determine which may be adapted to a specific purpose. Their peculiar characteristics must be studied in order to know which will best fulfill the conditions arising in actual practice. Experiments are necessary in which the oil is subjected to conditions approximating, as nearly as possible, to the conditions proposed in its actual use.

Saunier states[17] that "success depends largely on the skill of the manipulator; and if he is not endowed with the power of judging, _mainly by the taste_, whether oil satisfies certain prescribed conditions, he can never be certain of the result." As the author's abilities in this regard are not up to the required standard, and as some oils are sometimes in such a state of decomposition that even the odor is unpleasant, he has used other, and perhaps more satisfactory, methods of determining the relative values of the various oils.

The following experiments show the relative values of oils that have been, or may be, used in horology:

J. J. Redwood has made experiments on the action of oils upon metals, especially for the purpose of determining which oils were best adapted for use on the various metals and for ascertaining which oils were most suitable for mixing as lubricants. He has tabulated the results of his researches in two tables, which show that:[18]

_Mineral oil_ has no effect upon copper and zinc, and attacks lead most.

_Olive oil_ attacks copper most, tin least.

_Sperm oil_ attacks zinc most, copper least.

The experiments show, on the other hand, that:

_Bra.s.s_ is attacked most by olive oil.

_Copper_ is not attacked by mineral lubricating oil, least by sperm oil.[19] Dr. Watson states in regard to this action:

1. That of the oils used, viz., olive sperm, neat's-foot, and paraffine, the samples of paraffine oil on copper was least affected, and that sperm was next in order of inaction.

2. That the appearances of the paraffine oil and the copper were not changed after an exposure of 77 days.

He later[20] experimented further with the following results noted, after one day's exposure, with iron:--

1. _Neat's-foot._--Considerable brown irregular deposit on metal. The oil slightly more brown than when first applied.

2. _Sperm._--Slight brown deposit with irregular markings on the metal.

Oil of dark brown color.

3. _Olive._--Clear and bleached by exposure to light and air. The appearance of metal the same as when first immersed.

4. _Paraffine._--Oil bright yellow and contains a little brown deposit.

The action of oils on iron exposed to their action for twenty-four hours and on copper after ten day's exposure was found to have been:--

TABLE II.

ACTION OF OILS ON METALS.

------------+----------------+----------------- OILS. | IRON DISSOLVED | COPPER DISSOLVED | IN 24 HOURS. | IN 10 DAYS.

------------+----------------+----------------- Neat's foot | .0875 grain. | .1100 grain.

Sperm | .0460 " | .0030 "

Olive | .0062 " | .2200 "

Paraffine | .0045 " | .0015 "

~76. Various Experiments~ have been made by the writer with a number of oils that may be, or have been, used in horology, as well as with the princ.i.p.al watch oils on the market. At first he did not intend to mention the names of the manufacturers; but, after seeking advice of several eminent watchmakers, and on mature consideration, he decided to do so for the following reasons:--

1. The object of the Society before which these lectures were delivered[21] is "to promote and to secure concerted action for the purpose of _mutual_ improvement in the practice of our profession as horologists, by a study of both the practical and theoretical divisions of the science and art of horology; _to publish the results of such study for the benefit of all in the profession_; _to preserve the same for the use of our successors_; to elevate the standard of workmanship; and to encourage in the members a higher conception of what our art really is."

As this object cannot be attained without the names of manufacturers being mentioned in connection with their oils, the author considers that this is sufficient justification.

2. No injustice can have been done the manufacturers when the author states that the results obtained by him are not to be considered as conclusive evidence regarding the properties of the oils tested, as the samples he used may have been better than, or not so good as, the usual output of the manufacturers whose names were on the labels.

3. Some of the manufacturers of oils sent samples subject to the condition of the publication of the results, with the request that the oils should be submitted to test, and if found wanting, they (the manufacturers) certainly wished to know it.

TABLE III.

FOR REFERENCE.

[Transcriber's note: Table Split for Text file]

----------------------+----------------------------------------+ | MANUFACTURER. | +----------------------------------------+ SYMBOLS | | | EMPLOYED. | NAME. | LOCATION. | | | | ----------------------+--------------------+-------------------+ [B]E. K. w | Ezra Kelley | New Bedford, Ma.s.s.| | | | | | | [B]W. F. N. w | W. F. Nye | New Bedford, Ma.s.s.| | | | | | | [A]D. C. S. w | D. C. Stull |Provincetown, Ma.s.s.| | | | | | | [A]D. C. S. ch | D. C. Stull |Provincetown, Ma.s.s.| | | | | | | [A]D. C. S. cl | D. C. Stull |Provincetown, Ma.s.s.| | | | | | | [B]W. C. w | W. Cuypers | Dresden, Germany | | | | [A]B. & K. w | Breitinger & Kunz | Philadelphia, Pa. | | | | [A]S. B. & Co. wc |Stevenson Bro. & Co.| Philadelphia, Pa. | | | | [A]C. L. Co. w | Chem. Lub'g Co. | Brooklyn, N. Y. | | | | [A][C]C. L. Co. No . 1| Chem. Lub'g Co. | Brooklyn, N. Y. | | | | [A][C]Glyc | Bullock & Crenshaw | Philadelphia, Pa. | | | | [B][C]Alb. f | McKesson & Robbins | Philadelphia, Pa. | | | | [B][C]Alb. s | McKesson & Robbins | Philadelphia, Pa. | | | | [B][C]Sp | ----? | ----? | | | | [B][C]Ol | ----? | ----? | ----------------------+--------------------+-------------------+

---------------------+------------------------------------------------------- | OIL.

|-----------------------------+-------------------------- SYMBOLS | | | SOURCE.

EMPLOYED. | KIND. | NAME. |-------------------------- | | | GENERIC.| SPECIFIC.