Beystiman It's fun, it's light, [but] it has a hard time when its tries to get heavy.

Donald Seymour This is one of the best movies I’ve seen in a very long time. You have to go and see this on the big screen.

Ella-May O'Brien Each character in this movie — down to the smallest one — is an individual rather than a type, prone to spontaneous changes of mood and sometimes amusing outbursts of pettiness or ill humor.

Cristal The movie really just wants to entertain people.

Horst in Translation (filmreviews@web.de) "Mechanical Principles" is a 10.5-minute documentary short that shows us all kinds of mechanical movements from a machine. The director here is Ralph Steiner and even if this black-and-white sound film here is not his most famous work, then it is still somewhat remembered as an interesting piece of filmmaking from its time. "Its time" means 1930 in this specific case, so this one here is already over 85 years old. People with a bigger interest in mechanics and dynamics may have a great time watching this one, but to me it is really just another fairly forgettable experimental film and I see nothing truly memorable in here. I do not recommend the watch and **/***** is still fairly generous as this is a very monotone movie and actually should have run for no longer than 5 minutes. Thumbs down.

veronikastehr Working of machine resulted here due to the ''clarity'' of choice of motifs and photographs in an abstract contemplation about energy and eternal cosmic circular change. Painstakingly elaborated compositions of each shot stimulate the viewer to perceive the exactness according to which function various parts of every machine speaking at the same time about the way how the director Ralph Steiner works – avant-garde filmmaker active in the early 20th century. The same as in the working of machine, in this film Steiner left no room for improvisation. It is however interesting that the work as a whole looses the harshness of cold mathematical approach and gives the effect of visual poetic dedicated to the epoch of machines – constructed mechanisms that produce energy, invisible omnipresent power.

MartinHafer This film is from disc 7 of the collection entitled "Unseen Cinema: Early American Avant-Garde Film 1894-1941". It's a very esoteric collection of mostly art films and films of historical interest from the early days of film. It is NOT the sort of collection that the average person would consider even watching--which, I guess, makes me a weird guy.The film consists of cross-sections of various rotary and piston engines at work. The shots are all closeups and are set to music that seems quite fitting to the slow-speed action. It's all a bit hypnotic (or boring depending on your perspective) but certainly NOT a film that most folks would rush out to see. As it really defies my ability to give the film a numerical score, I'll just say that it was different...

Michael_Elliott Mechanical Principles (1930)*** (out of 4) Imaginative short from Ralph Steiner is a 100% visual feast as we see close up shots of pendulums swaying, pistons going up and down or side to side and various other mechanical operations. This is just one of many shorts including on the UNSEEN CINEMA set, which also shows up on Turner Classic Movies ever so often. This is a pretty entertaining set of avant garde films and this one here contains some of the most imagination. I will admit that at 10-minutes I began to feel a bit drained towards the end but there's no question that the director put a lot of thought into the final product. I find that many avant garde films just try to show random images in a variety of ways just so the finished product can have some sort of strange or weird feel to it. That certainly happens here but the exception is that every shot seems to have been well thought out and placed in an order that makes the film run smoothly and not once do we just feel like we're seeing stuff pieced together without any thought. This is where the imagination comes from and what makes the film really set itself apart from others like it. Some reviewers have mentioned the possible influence on Chaplin's MODERN TIMES and that's certainly possible.