at great expense imbedded in the earth, one at each extremity of the line, to mark the initial points. On placing compasses over these points to determine the bearing of the base, we were extremely perplexed by the unaccountable local attraction that prevailed; and were compelled, in consequence, to select a new position. This we finally concluded to adopt between Fort Point and Saucelito; but, on attempting to measure the base, we were deterred by the unexpected depth of the water intervening, which, to our surprise, was considerably over the chain-bearers' heads. Disliking to abandon our new line, which had been selected with much care and at great expense, I determined to employ in its measurement a reflecting instrument, used very successfully by the United States Coast Survey. I therefore directed my assistants to procure me a "HELIOTROPE," but after being annoyed by having brought to me successively a sweet-smelling shrub of that name and a box of "Lubin's Extract" to select from, it was finally ascertained that no such instrument could be procured in California. In this extremity, I bethought myself of using as a substitute the flash of gunpowder. Wishing to satisfy myself of its practicability by an experiment, I placed Dr. Dunshunner at a distance of forty paces from my Theodolite, with a flint-lock musket, carefully primed, and directed

him to flash in the pan, when I should wave my hand. Having covered the Doctor with the Theodolite, and by a movement of the tangent screw placed the intersection of the cross lines directly over the muzzle of the musket, I accordingly waved; when I was astonished by a tremendous report, a violent blow in the eye, and the instantaneous disappearance of the instrument.

Observing Dr. Dunshunner lying on his back in one direction, and my hat, which had been violently torn from my head, at about the same distance in another, I concluded that the musket had been accidentally loaded. Such proved to be the case; the marks of three buckshot were found in my hat, and a shower of screws, broken lenses and pieces of brass, which shortly fell around us, told where the ball had struck, and bore fearful testimony to the accuracy of Dr. Dunshunner's practice. Believing these experiments more curious than useful, I abandoned the use of the Heliotrope" or its substitutes, and determined to reverse the usual process, and arrive at the length of the base line by subsequent triangulation. I may as well state here, that this course was adopted and resulted to our entire satisfaction; the distance from Fort Point to Saucelito by the solution of a mean of 1,867,434,926,465 triangles, being determined to be exactly three hundred and twenty-four feet. This

result differed very much from our preconceived ideas and from the popular opinion; the distance being generally supposed to be some ten miles; but I will stake my professional reputation on the accuracy of our work, and there can, of course, be no disputing the elucidations of science, or facts demonstrated by mathematical process, however incredible they may appear per se.

We had adopted an entire new system of triangulation, which I am proud to claim (though I hope with becoming modesty) as my own invention. It simply consists in placing one leg of a tripod on the initial point, and opening out the other legs as far as possible; the distance between the legs is then measured by a two-foot rule and noted down; and the tripod moved, so as to form a second triangle, connected with the first, and so on, until the country to be triangulated has been entirely gone over. By using a large number of tripods, it is easily seen with what rapidity the work may be carried on, and this was, in fact, the object of my requisition for so large a number of solar compasses, the tripod being in my opinion the only useful portion of that absurd instrument. Having given Lieutenant Root charge of the triangulation and detached Mr. Jinkins with a small party on hydrographical duty (to sound a man's well, on the upper part of Dupont Street, and

report thereon), on the 5th of February I left the Plaza, with the savans and the remainder of my party, to commence the examination and survey of KEARNY STREET.

Besides the mules drawing the cart which carried the transit instrument, I had procured two fine pack-mules, each of which carried two barrels of ale for the draftsmen. Following the tasteful example of that gallant gentleman who conducted the Dead Sea Expedition, and wishing likewise to pay a compliment to the administration under which I was employed, I named the mules "Fanny Pierce,"

and "

Fanny Bigler." Our cortége passing along Kearny Street attracted much attention from the natives, and indeed, our appearance was sufficiently

imposing to excite interest even in less untutored minds than those of these barbarians.

First came the cart, bearing our instruments; then a cart containing Lieutenant Zero with a level, with which he constantly noted the changes of grade that might occur; then one hundred and fifty men, four abreast, armed to the teeth, each wheeling before him his personal property and a mountain howitzer; then the savans, each with note-book and pencil, constantly jotting down some object of interest Dr. Tushmaker was so zealous to do something, that he pulled a tooth from an iron rake standing near a stable-door, and was cursed therefor by the illiberal proprietor), and finally, the Chief Professor, walking arm in arm with Dr. Dunshunner, and gazing from side to side, with an air of ineffable blandness and dignity, brought up the rear.

This

I had made arrangements to measure the length of Kearny Street by two methods; first, by chaining its sidewalks, and secondly, by a little instrument of my invention called the "Go-it-ometer." last consists of a straight rod of brass, firmly strapped to a man's leg and connected with a system of clockwork placed on his back, with which it performs, when he walks, the office of a ballistic pendulum. About one foot below the ornamental buttons on the man's back appears a dial-plate connected with the